Can an apple move the earth? Physics says it can. The power that gave an apple the ability to move the world, also gave us humans the capacity to make use of the natural laws and be a true vicegerent on the earth.

In a universal arrangement of objects, from the smallest to the largest, in terms of length, time, and mass, where is the human located? In between the diameter of an atomic nucleus (10-14 meters) and the distance of the farthest galaxy from the earth (1026 meters), the human being occupies a zone between one and three meters. The human lifetime can be measured to be around 109 seconds in temporal length, to the duration of a ray of light passing through a proton (10-24 seconds), to the age of the universe (1017 seconds). And the human mass is located around a 102 kg zone, on a scale from the mass of an electron (10-31 kg), to the mass of the Milky Way galaxy (1041 kg).

Based on this data, understanding the human that is trapped in this enormous universe is crucial. Humans are just a speck, jammed between mote and sphere, living in a frail state of weakness and poverty. “Do not strut about the earth in haughty self-conceit; for you can never split the earth (no matter how hard you stamp your foot), nor can you stretch to the mountains in height (no matter how strenuously you seek to impress)” (Qur’an 17:37).

Humans, who need a vast amount of grace and support, are in search of answers to improve themselves. “Who am I?” they often ask; “where am I?” As scientists and researchers discover the excellence of the universe’s artistry, we begin to comprehend just how blessed humans are. Within the laws of science lie the answers to our questions. Laws are relative principles that operate according to the constants wisely built into the universe. These laws are veils to the majesty of creation. Each law is created anew every moment, thus we perceive them as if they are eternal patterns. For example, the human body gravitates to the center of the earth with a force equivalent to their mass multiplied by the average gravitational velocity of the earth, which is 9.8 m/s2. The law of gravity is created every moment in such fine measures that it is possible for us to walk on the ground.

It helps to remember Newton’s three laws in physics. The first is the principle of inertia, which states that unless there is an external force, or if the sum of all forces cancel each other out in direction and size, then an object is either at rest or moves at a constant velocity. The second law is that force equals the mass of an object multiplied with its acceleration. And the third is the action-reaction principle, which states that when a force is applied to an object, the object exerts a force in opposite direction, equal in magnitude. This means that when an apple is thrown into the air, and the apple accelerates in opposition to gravity, the earth is distanced from the apple with the same amount of force. Similarly, when the apple falls down because of gravity, the apple is also pulling the earth with the same magnitude. If this was to repeat constantly, theoretically a movement like the one made by a yo-yo should have happened between the apple and the earth. Because of its huge mass, the earth’s acceleration is very small, thus this yo-yo movement would not be felt. An object as small as an apple actually moves an object the size of the planet. This means that the power that gave an apple the ability to move the world, also gave us humans the capacity to make use of the natural laws and be a true vicegerent on the earth.

Nothing in the universe has been created in vain – all phenomena occur because of a purpose they are assigned to fulfill. In a universe in which everything is bound by a complicated web of laws that are created without a moment’s lapse, humankind surely has a significant role to play in the unique position with which they are graced. This position undoubtedly requires a sense of humility in the face of all the grandeur around us, yet also being aware of our given capacities, which enable us to master over all existence.

How good are we aware of the operations of systems and mechanisms that make us walk?

Costly research and development efforts are under way in centers throughout the world seeking to build walking robots by mimicking human mobility. After 14 years of research, automotive firms built Asimo, a robot which can walk bipedally and climb stairs like humans. Even though the moves Asimo could make matched those of a one year old baby, it was still considered a great success for the robot technology.

Hardships encountered during these research projects proved walking to be a great miracle, apart from normal habits of movement. We often become aware of how extraordinary movement is and that the moves we repeat hundreds of times, such as walking, running, bending, sitting and standing, are blessings granted to us only when we see someone who has lost some of their mobility.

That humans can walk bi-pedally is truly exceptional. Most organisms have a front leaning skeletal structure and walk on four extremities; they only stand upright when absolutely required to, since it is very difficult for them. Human ability to stand upright and walk on two legs truly signifies them as special amongst creatures, and sets them apart from all of creation. The lively, regal posture of dexterous bipedal humans constitutes very important evidence showing they are “the most superior of all creatures.”

The multifunctional, flexible nature of our skeletal system enables us to complete very simple moves automatically. Walking seems to be a very easy task, however, it occurs as a calculated outcome of many factors, such as determination of stepping distance, the toning of corresponding muscles of the same and opposite direction, relaxation and contraction levels, and relocation of the body’s gravity center.

Walking takes place via the coordinated works of the locomotor (musculoskeletal) system, motor control system, and balance-coordination system.

Locomotor (musculoskeletal) system

The framework of the human body is built together with 206 bones of variable hardness. With their strong nature and capacity to endure extra weights, bones takes up 20% of a body’s mass, and are the major load bearing part of the body’s structure.

The main part of our skeleton is the vertebral column. It consists of 33 small bones, known as vertebrae, positioned on top of each other. Wear-preventing discs are found in between vertebrae to protect against motion related wearing over time. As the vertebral column holds the weight of the upper body, it is created in a way to keep the body upright. The spinal cord inside the channel that is surrounded by the vertebral column is a very important signaling network providing coordination between the brain and other organs.

Joints and ligaments are among the moving parts of our body. The most important joints for walking are the hips, knees, and ankles. The curvy shape of the foot and its contact to the ground at three spots supports bones against body weight and helps with balance. This is why flat footed people struggle with walking and get tired easily. The curves of our spine at the neck, back and waist regions, and the hips, knee joints, and curvature of the foot, are perfectly shaped for standing upright and walking.

In order to move we need a muscle system along with the skeletal system. Muscles are made up of thousands of contractible muscle fibers. There are more than 6 billion muscle fiber motors in the human body. We walk, run, eat, breathe, talk and do many more moves by using ability granted to muscles. Approximately 35 muscles in each leg, and around 100 muscles in the whole body, function during walking.

Ligaments and tendons are links that secure bones and muscles together; they also help to stabilize joints, thus when standing, joints remain in place without muscles contracting.

Four different mechanisms are involved in walking:

1. Proper upright posture and maintenance of balance during walking
2. Forward motion of body via muscle power
3. Reduction of shock-impact effect while stepping
4. Maintenance of motion with the least amount of energy.

A series of movements is generated in the legs to provide a forward motion and these are constantly repeated. These constant repetitions are called the “walk cycle.” The “passing pose” is defined as the time frame when the leg is in the air, and the contact pose is the phase during ground contact. In the middle of the contact pose, even though body is in balance, because of the forward momentum of the body, balance is lost, thus the body leans forward. Balance is then restored by stepping on the ground with the leg in the air. As a result of this rhythmic loss and restoration of balance, the body moves forward.

In a person standing upright, the center of gravity is in front of the fifth vertebra. At the start of a walk, the body leans forward to carry the center of gravity towards the front; then the initiation of the motion via forward transfer of the power with toes and joints takes place, followed by the lifting of the heels, the bending of the knees, and the lifting of the foot, thus displacing the center of gravity of the forward leaning body towards the front.

Balance should be maintained when one leg is lifted in order to let the other leg carry the load of the body’s weight. The gravitational center of the body is located in the distance between the two legs since each leg is located on the side. Body balance is maintained by the contractions of dorsal muscles located across the side of the stepping foot, working in parallel to support and transfer body weight to the foot via the hip and femoral muscles. These events happen so quickly that we often do not even notice all the complicated processes.

The great Sufi figure Abdul-Qadir Gilani was often asked questions such as, “Master, show us a miracle.” He would stand up to walk three to five steps and sit back down. Everybody was confused, looking at each other. One person among them was heard saying, “Master, excuse us but we can all do that as well.” Gilani replied then, “Is there a greater miracle than walking? You see it, but do not understand.”

Motor control of walking

Bodily motions are controlled via the primary motor centers that are located on the side and cortex region of the brain. These centers are created in a way to prepare and organize motor programs involving body movements, and to integrate them with the proprioceptive memory. This synthesis of information enables the adaptation of motor commands to the present posture of the legs and arms regarding intended moves.

A desire to make a move is a necessary prerequisite for the stimulation of muscles pertaining to it. If we want to hold something, we can easily do it; when we want to raise our arm, our elbows bend; to run or walk, our leg muscles start to move and work. How do all of those moves happen? Is our desire enough to do so? Can the guidance of all the bones and muscles, working together towards the same target, happen by itself or occur via coincidences?

In order for muscles to move, our thoughts must be relayed to them and this is provided by the nervous system and nerve network. There is an amazing communication network present in our body. In case of an intended move, an electric signal is sent by the brain. During this journey, which seems to be complicated, the signal arrives at the spinal cord and then quickly diverts to the corresponding organ. Millions of motors that make up the muscle are stimulated by the electric signal, contracting the fibers instantly upon reception of the signal. In order to do a coordinated move, it is necessary to know the related body organs’ positions and their relations to each other. Millions of transmitters that provide this information have been placed throughout the body. This data come from the eyes, the inner ear’s balance and sensory organs, muscles, joints, and skin. There are billions of micro receptors located in muscles and joints programmed to send instantaneous positions of the body to the central nervous system. In every stage of a move, the positions of the muscles are reported instantly to the command center by these micro receptors inside the muscles. New commands are given to the muscles based on the assessments made here. This way, each second, billions of bits of information can be processed and assessed.

The cerebellum is another center that is in charge of functions such as maintenance of balance during walking and standing, carrying out proper and coordinated moves with visual control, providing coordination among muscle groups, promptly starting and stopping movements, and the maintenance and organization of normal muscle toning. The cerebellum is tasked primarily with hastened muscle activities like running, typing, and talking. Thus, fast moves necessary for the balance system are sustained properly and successively without abnormal oscillations.

Specific motion templates have been programmed in the spinal cord for all muscle-covered regions of the body. Rhythmic movements, such as forward and backward motion of the legs and arms, and coordinated activities of other body parts in tandem with walking, are controlled here. The task to control repeated moves like walking is assigned to the nerve network consisting of the spinal cord, brainstem and cerebellum.

Balance and coordination system

One of the requirements to walk and move is to stay in balance. Despite our advanced musculoskeletal system, without balance, this system of ours would be useless, or even dangerous.. Our balance system, which is in charge of the instantaneous control and fine adjustments regarding our body, is granted to us as a blessing of Divine compassion.

There are three systems that provide data involving the positions of the head and body: vestibular system (the apparatus of the inner ear), visual senses, proprioceptive senses

The vestibular structures are an essential part of the balance system. They are found in the inner ear, and are small and complicated systems. This 6.5 mm diameter wide system is composed of semicircular channels that contain specific fluid and ciliated sensory cells that cover the inner linings of the channels. This system constantly reports information involving our status in the outer world and instantaneous changes to the balance system.

When we move, the fluid inside the semicircular inner ear channels get displaced; this motion vibrates the cilia. This vibration causes an electric signal to generate in the cells. This electrical signal is then transmitted to the cerebellum; received information gets evaluated instantly in the cerebellum. This system is created to function autonomously without our will and control. When this system is impaired, balance disorders occur, such as dizziness.

Information regarding our position in the environment and the relative status of the environment according to us is sent to the cerebellum and brainstem via our visual senses.

Proprioceptive senses are formed via the activities of tension receptors built in muscle fibers, tendons and joint capsules. These are sensitive to motions and positions. These receptors regularly provide information to the central nervous system. The cerebellum receives information from all the muscles and joints of the body, including the eyes. These inputs are analyzed very promptly at the cerebellum, and the relative gravitational position of the body is finely calculated, thus the proper motions of muscles are determined. The resulting response is relayed towards muscles by nerves. These events take place in a time frame that does not even last for a hundredth of a second. We easily walk, run, and do complicated moves without feeling any of these activities happening inside us. Yet the calculations taking place in our body even for a single moment of those movements can fill thousands of pages.

To understand the fascinating side of our ordinary movements, let’s consider a person climbing up the stairs. First, the eyes scan the surroundings, then the three dimensional information of positions acquired from the materials and belongings in the environment are transmitted to the brain. Once received, the information is analyzed and the necessary commands are sent to the target organ from the motor centers of the brain. Commands passing through related tracks and centers finally arrive at the musculoskeletal system. Many factors, like the height of stair steps, length and depth of the foot step, center of gravity and position of the body, are calculated and determined almost instantly.

Proprioceptive signals constantly report the positions of organs, like the arms and legs, to the command center. Inner ear receptors are in charge of the prompt transmission of information necessary for balance, like motion, speed, and direction of the body. These inputs are calculated in milliseconds at corresponding centers in order to maintain the coordination and harmony of the entire body. A person who is running up the stairs may think to jump a couple of stairs. This change of command is rerouted to the locomotor system as a new and different command from the brain. All of these processes are completed in centiseconds. In the mean time, the head, shoulders, and arms are employed for rhythmic oscillations in order to adapt to the overall body momentum.

In conclusion, standing and walking are miraculous and take place via thousands of interrelated activities. Nonetheless, we usually do not notice any of the thousands of processes that are constantly taking place. One hopes that every blessing we have is seen through the window of thanksgiving and appreciation.

Kemal Serce is a professor of veterinary medicine in Bursa, Turkey.

No matter how fast or how far a person runs, the horizon will always be beyond them. This being the case, the real distance and depth of the horizon is inside a person, it is in their mind and perception…

A race I will always remember

Not too long ago, when I was still a little boy, I found myself running from my father’s village to my mother’s, and from my mother’s to another and to another, in the hope of catching up with something that was neither a ball, some other toy, nor a bird, but rather the point, the line where the sky seemed to touch the earth. We call it the “horizon.” That line, that “place,” first presented itself to me hiding right behind the trees to the left of my father’s house. I started out that day walking rather leisurely because the distance between me and the horizon seemed so short. When I observed that the sky had moved, or rather seemed to have moved further away, I hastened my steps. Then I noticed that the sky moved further and further away. Well, being determined to reach the place where the sky certainly touched the ground, I kept walking faster and faster until I found myself running.

I ran for quite a while until I realized that “there”, where the sky and the earth met, was still further away, that it would take me more time and effort than I had thought. I went back—I had to go back—to my father’s village, back to my usual village life because I saw that perhaps much more was involved, that maybe much more effort was called for in order to achieve what I desired, namely, to get to the point where I could touch the sky, where I could climb the sky. I went back to the ordinary, the normal life and experience of the village and of my people. But I did not tell anyone, I did not discuss the experience with anyone, even though I did not stop and could not stop thinking about it. I thought to myself that perhaps a week, a month, maybe a year would suffice for me to reach the place where the sky and the earth embraced. I was absolutely certain that right there in front of me, over there, not too far away, the sky touched the ground. And I thought that perhaps all I needed to do was keep walking, keep running, and keep racing forward, without stopping, without interruptions, without distractions in order to get to where the sky kissed the ground.

Today, thirty-five years later, I have realized that I was not wrong. I was right. The sky did touch the ground. It touches the ground all the time. You may ask “but where and how?” The sky touches the ground in our perception. Look across from your window into the distance. What do you see? Or, go outside and look in the distance. What do you see? The sky is right there, over there, touching the ground, the road, the houses, the trees, the mountains, the sea, and remaining there. But keep in mind that this is all happening in our perception. In perception, things are the way they appear, the way they seem. No rigorous, critical thinking is involved. And this happens so many times, and in fact is happening now; it happens every time that we are not thinking deeply, with attention and effort. It happens every time we fail to allow other perspectives, other possibilities and other possible interpretations to emerge.

The sky touches the earth, embraces and kisses the ground, right there in a fixed position, as long as you do not move. Once you move, it moves. And when you run after it, it too runs, not towards you though, but rather away from you. If you stand still, it stands still. If you stay where you are, it remains where it is. If you move even an inch, it will move. It will never allow you to catch up with it, to touch it; it will never allow you to possess it, to tame it; it will never allow you to take possession of it. And yet, it is always there, “putting everything into perspective.” By that I mean the horizon enables us to see, for without horizon one cannot see much of anything. Think about it! Everything presents itself in horizon. Everything dwells in the horizon, everything is within the confines of the horizon, and depends more or less on this phenomenon. And if I may borrow an expression from Saint Paul’s speech at the Areopagus (Acts 17:28) and be at liberty to use it as I see fit in this context (just as some scholars say he himself was at liberty to do with the same expression from the writing of Epimenides of Knossos (6th Century B.C.)), one can say that “that in which we live and move and have our being” is the horizon.

Standing still, remaining in one fixed position is not in the nature of the horizon. Its every stop (or what appears to be its end, its boundary) is temporary and transitory, like a pilgrim’s stop on a journey whose destination is still far away. It keeps moving, and it invites us to keep moving too, keep working, keep meeting people, keep exploring, keep digging, keep sowing, keep cultivating, keep harvesting, keep looking, keep reading, keep writing, keep thinking, keep talking, keep wondering.

We hear, not infrequently, the expression, “on the horizon/in the horizon.” What does it mean? It means in view, in the possible future, in sight. That which is in or on the horizon appears close, and seems to be approaching; it is as if it’s right there among the things that one hopes to do soon, as something squarely within one’s reach, among the things that one’s abilities can handle. What is in the horizon, then, is something that appears “present” and seems quite achievable.

What is a horizon? And what does it do?

A horizon is inseparable from a living, perceiving human being who is in the open or in the frontier of the open. There are no horizons in closed spaces, closed places. The distance between a living human being and the line where the sky and the earth meet is very wide. It is infinite. It is far, far away. You can only measure it with your eyes, your mind and your soul. You can figure out how long it is only to the extent that your eyes, your mind and your soul can go. An application of any other measuring device will only frustrate you because the moment you start going after it to measure it, it will recede. But the truth is that what you are actually seeing of the horizon is only a small part of it. The bigger part is on the other side of the horizon. Every horizon has at least two parts: a front and a back. The front of the horizon consists of the part you are seeing, and its back consists of the part hidden from you because of the hills and mountains, the earth, the road, the trees, the sea. In fact, the line where the sky seems to touch the earth is really only a perceived curve or a perceived point of contact, but the horizon really goes far and farther away, without end: it stretches into infinity.

All the things we are seeing are in fact standing in the way of the horizon. Similarly, all the things we are thinking right now, all our thoughts and ideas, everything that is presently on our minds can be an obstacle to a deeper and fuller understanding and appreciation of the horizon. We have to let go of all of these things in order to begin to have an idea of the depth and richness of the horizon.

For now, let us focus on the part of the horizon that is visible to us. It is a world, the world that we live in or would like to live in. Normally, it consists of people, people of different religions and/or of no religion at all, people of different languages and cultures, different experiences, different states and walks of life, different situations and aspirations, people driven by different desires, values and visions, people of very deep opinions, inspirations, beliefs and deep convictions other than our own, people heading in a thousand and one directions. This world, this visible side of the horizon also includes animals of many different types and habitats, which eat different kinds of food and have different spans of life. It also includes many different trees, bushes and flowers, and different types of grasses, etc. Mountains and hills and valleys too, rivers and big oceans, streams and creeks, are all part of this side of the horizon. Small and big houses, low and high buildings, shelters and palaces, mud houses and ghettoes are all part of this side of the horizon that we are seeing. But we do not actually see everything that we know is out there, that is all around us, that is over there in front of us…

How do we even know that there is anything out there, that other people are out there? A long walk, travels, meeting people, doing business with people, education, etc. confirm that there are other people out there, other lifestyles, other ways of thinking, other ways of doing things, other attractions, other things that people consider as very precious and worth dying for. We read about these things, have actually met and seen them with our own eyes, have lived with people of different orientations and values, have had some great opportunities to exchange ideas with them. But neither our reading and studying nor our investigative and explorative eyes can exhaust the visible side of the horizon because even the visible side has its own invisible aspects and invisible faces. Let us take for example persons, situations and objects.

From time to time, a person whom I have known for many years, not only surprises me, but also seems to be a surprise to herself/himself whenever s/he says something or does something I could never have thought or imagined her or him doing. And people of this nature are not uncommon.

How about situations? They are similar. Even the most familiar situations often have aspects that are new and different, which we can see if and when we look with more attention and care. And the moment we become used to these, even newer different aspects of the same situation emerge. The same goes for things such as books, clocks, chairs, doors, and so on. A book often presents us with information that we did not see the first time we read it. And if you read it again, you will again see something you missed the second time you read it. If you wish, you can read it again and again, and you will see something new every time. The book will never fail to make you see something new and/or think something new.

Can a chair or a door do something similar? That is, can a chair or a door make you see something new or think something new every time you encounter them? Let us see. A chair, unlike a book, seems to have no generative power. It seems mute and sterile. But can a chair speak and make us think? The answer is yes, it can speak and make us think. No one would disagree that the chair of Pontius Pilate, the chair of a Court Judge, the chair of Saint Peter, and so forth do have a powerful message. Although these chairs I have cited are special, every chair can say something to us and really make us think. For example, chairs for children and for adults make us think different thoughts, which by the way, make us give children appropriate chairs and to adults what is suitable for them. If we did not think differently of these chairs, chances are we would give adults the chairs meant for children and vice-versa, or give the same kind of chairs to everybody, children and adults alike, seriously compromising comfort. And some chairs would even fall apart (that is, if children’s chairs are given to heavy people like me to sit on).

Doors too make us think. For example, the Door of No Return in Goree Island in Dakar, Senegal, and the Door of Hope in Johannesburg, South Africa, makes every visitor think. But again, although these specific references are special, every door, including those that may seem unimposing and insignificant, can really make us think. Every door has a message.

The bottom line is that even the most visible side of the horizon can have aspects that may not be totally obvious and immediately accessible. Therefore, the visible, that which seems completely clear can still make us think because it often has layers, folds, dimensions, messages that lie beneath its surface. There are always other meanings, other messages behind the obvious. And the moment we finish harvesting one message, the moment we finish reading one meaning, the horizon presents us another one, and yet another, and so on and so forth. Inexhaustible indeed, this horizon can constantly give new meaning, hope, color, shape, style, texture, depth, taste and strength to our lives for endless joy and delight, even under very difficult circumstances. Why? Because the horizon has power to liberate us from the present, the immediate, the obvious. As it draws back, so to speak, that is, when we attempt to respond to its invitation into the open, when we dare to go after it, go with it into the deep, when we allow ourselves to move with it and flow with it, then it can open new doors, generate new ideas, launch new beginnings, reveal inroads, illuminate new bridges, disclose exits, uncover new faces, make terrains of other possibilities visible, make cooperation and collaboration possible, make teamwork possible, bring along other solutions, other fertile soils. With the horizon, there are no closed doors, no human being is a finished project, no done deal, no finished once-and-for-all discussions, no insurmountable barriers. The horizon’s open field stretches into infinity.

All of this is but an invitation to read between the lines, i.e., “to resist simplistic interpretations that dogmatically ascribe fixed significations to [things]” (G. Weiss, Refiguring the Ordinary, Indiana University, Bloomington, 2008, p.58).

It is about the need to go on researching other possible meanings and interpretations of a text, to go on searching for other possible answers to certain problems, to appreciate the expanding limits, and to devote more time and energy to the lifelong project of exploration of self and of the world (and of God) (see P. Okogie’s “Horizon: the birthing world” in the Journal of Horizons of Horizons, Vol. 1, no. 1, Duquesne University, Pittsburgh, 2012, p.10).

Rev. Dr. Okogie is Assistant Professor of Philosophy and Bioethics, University of Saint Anselm, Rome, Italy.

Let us imagine the earth as a small sphere before us. If we throw an object from the North Pole toward point A on the equator line, the object follows a curved line towards the right side and reaches point B, not point A. Likewise, an object thrown from the South Pole towards the same point A will follow a similar line curved in the opposite direction. These cases have a common point. An object rolling on a rotating ground moves on a curved line. This curved line, instead of a straight one, is explained with reference to the force of acceleration. This force is named after the French engineer, Coriolis who explained it in 1835. If this force-which is generated by the earth rotating around its own axis-did not exist, then air movements and ocean currents, and consequently the climate conditions of our world, would be different than they are. The objects in our example, thrown from the two poles, go in different directions, because the world rotates counter-clockwise when looked from the North Pole, and clockwise from the South Pole.

The air over the equator receives the sun’s rays at a broad angle. It rises up after gaining heat and is replaced by colder air coming from distant latitudes. Air convection begins in connection with these heat changes. So if the world did not rotate, the air on the Poles would get heavier with cold air and come down. Then, it would be replaced by hot air from lower latitudes. The air at the equator would rise up with gaining heat and would move until reaching the Poles where it would come down after losing heat. Then, it would return to the equator, this time very close to the ground. In this case, the world would probably be an uninhabitable place with cold and fierce winds blowing all around. And of course, the side facing the sun would be very hot and the other side would be very cold.

Instead, the Coriolis effect makes these great atmospheric air masses move over our rotating earth. The hot air rising up from the equator moves towards the poles with a curved course thanks to the Coriolis effect (Figure 4). As this air current approaches the latitudes around 30 degrees, it loses heat and descends. A part of the descending air begins to move back toward the equator, but it follows a curved line again owing to the Coriolis effect. So this last curving forms the “trade winds.” In the past, sailing ships traveled from Europe to America for the purpose of trade; thus, these winds were named as trade winds. This air circulation between the equator and the 30-degree meridians is known as Hadley circulation. These air currents cause heavy rainfall in the equatorial region and the consequent formation of rain forests, which are considered as the lungs of our planet, and also they cause the formation of deserts around the region where the dry and hot weather are pure blessings for us. They are a blessing because the airborne dust rising from the desert fertilizes the rainclouds and plays a critical role for rainfall.

The air over the poles becomes cold, and it causes another air current as it becomes heavier and starts to descend. As the lowered air moves toward the equator, it changes course with the Coriolis effect. At the same time it begins to gain heat and ascend. At the latitudes where water ascends by gaining heat, a rain climate prevails. This polar air cycle is seen between latitudes of 60-90 degrees.

Some part of the air current, which descends down around 30 degrees of latitude, moves toward the poles at a low level. Also, some part of the air which comes from the poles and ascends begins to move towards the equator. So a third air cycling begins between the altitudes between 30-60 degrees. The “western winds” are brought forth from this third cycle. During the time of sailing ships, these winds were used to traveling from America to Europe (Figure 4).

In order for these air cycles to happen, the earth’s rotation around its own axis is not sufficient; its speed and atmospheric mass also play an important role. If the earth rotated slower, the Coriolis Effect would be too weak to give way to a triple air cycle. For example, since Venus rotates too slowly, there is only a single air cycle in its atmosphere. Another factor, as we mentioned, is the mass of the atmosphere. Since the atmosphere of Mars is thin and its mass is relatively less, the Coriolis Effect is too weak and there is only a single air cycle.

Coriolis Effect prevents the air current from following a straight course and the isobars form twisters as they proceed. Therefore, hurricanes in the Northern hemisphere move counter-clockwise, and those in the south move clockwise (Figure 5). Naturally, these main atmospheric movements are not the only ones. A region’s climate is dependent on several factors such as landscape, night-day heat differences, and the like. Therefore, the climatic conditions on the earth have a very complex structure. Even when we consider just these few factors discussed here, it is evident that there are countless parameters that make human life possible in our planet, and each one is finely adjusted. Even slight changes in rotation and the mass of the atmosphere would result in a dramatically different planet Earth.

The ocean currents

Movement of air masses affects the water on the ocean surface as well. Thus, wind-generated surface currents are born. These currents are parallel with the relevant winds. It is a well-known fact that these huge bodies of water change the climate of the regions they pass. Therefore, two places at 54 degrees of latitude show a surprising difference: there can be a polar bears’ park in Ontario, whereas palm trees and tropical fruits can grow in Belfast thanks to the Gulf Stream. There are other warm ocean currents that pass from Brazil, and the north and south of the equator. Some of major cold surface currents pass from Labrador, Canada, the Falkland Islands, and Peru. Warm currents soften the climate of the regions they pass, while cold currents provide sea creatures with rich food, and they are important areas of fishing.

The impact of the wind on ocean water normally reaches as deep as 100-200 meters, and even 1,000 meters in some cases. The Coriolis effect has a determining role on the direction of the currents. These currents on the move make a turn when their way is blocked by land. Thus, the succession of ocean currents becomes a cycle, and they form the great current cycles named as “gyre.” They turn clockwise in the Northern Hemisphere and counter-clockwise in the south.

There are five main ocean circulations on earth and each of them consists of four streams. These currents are at the north and south of the Atlantic Ocean, the north and south of the Pacific Ocean, and one in the Indian Ocean. The North Atlantic circulation is made up of the Northern Equator Current, the Gulf Stream, North Atlantic Current, and the Canary Current.

With the Coriolis effect, a blessing of wondrous scale, food chains are brought to life in the ocean and around coastal regions. The ocean waters are set in motion by the winds generated by the Coriolis effect, but they do not strictly follow the winds that activated them. With a deflection of nearly 45 degrees they move right in the Northern Hemisphere and to left in the Southern Hemisphere.

The effect of the winds weakens in the deeper ocean waters, and then the Coriolis effect becomes dominant. Thus the direction of ocean water carried in the Northern Hemisphere is vertical to the wind direction and towards the right. This condition causes ocean waters to be pushed towards the circulatory center, and the water level there rises about 2 meters.

As rising waters move down with the effect of gravity, the Coriolis effect comes to the stage again to give way to another current in the same direction within that current. The waters that were rising toward the center begin to sink, and they form a new vertical current. For the same reason, the separation of the water current to the right and left directions around the equatorial regions gives way to the waters at the bottom which then come to the surface. At these places, the water level decreases a little. This “upwelling” phenomenon has very important results. Dead organisms sinking down are broken down by bacteria in the deep waters. When this nutrient-rich water returns to the surface, it is a great blessing for so many sea creatures. It is a striking fact that the rotating of the earth is a means for providing many living beings with sustenance. All of these finely adjusted balances on our planet, which we mostly take for granted, provide reflecting minds with food for thought.

Dear Peter! I, your muscular system, would like to talk to you today; I allow you to walk and do all kinds of movements very easily. In the most recent essay of this department, the skeletal system, which works together with me, discussed how it protected your body and enabled you to stand straight and firm. Sure, this is true. However, as you know, huge rocks and trees can stand straight, too; but they do not have what you do-the ability to move. They are rigid and inflexible because they do not have a system that allows them to move.

You on the other hand, as the most splendid creation in the entire universe, have mobility. All animals have mobility at different levels, thanks to the muscular tissues, which work dynamically behind all the moving organs. However, you, human beings are like neither the animals nor the plants. You have not been created to live like a tree that is pegged down in earth or like an animal that unconsciously tries to meet only its biological needs. Our Designer, God, has made you and your descendants the most important of all creation. He has given you qualities that help you to discover the world, learn, invent and establish new civilizations. To realize such potential and to carry out such duties, you need to first have the freedom to make changes in your small immediate world, which can only be done through motion. In order to enable you with this ability to move, my Creator has put me at your service. I am a system that comprises hundreds of muscles and millions of packed cells.

My most important feature is the cells that move by burning sugar, like a motor consuming fuel in order to work. My cells can shorten and lengthen thanks to the intracellular fibrils (myofilaments) that contract and expand. As a result of each contraction, I pull the bone or the organ that I am attached to and cause it to move or change shape. With the exception of your heart, your bones and organs cannot move on their own. Their ability to move depends on the nature of the muscle they are attached to.

Indeed, I can be called both an organ and a form of tissue. I can use my contraction ability not only as muscle tissue, but also as an organ and a system which runs throughout your body. That is the reason why I appear in so many different types and shapes of muscle bundles. Let me give you an example to help you better understand what a muscle consists of: Let us imagine that a thin thread is like a basic muscular cell. Let us now bring together a great number of threads and make string out of them. Then, let us bring together those strings and make a clothes line. Next, let us bring together a great number of clothes lines and make a very thick rope. Now, imagine this thick rope as a muscle and an organ. Yet, this example is too basic compared to the sophisticated muscle.

Very thin cotton fibrils make up the thin threads. In the muscle fiber, like those cotton fibrils, there are two filaments formed by the two types of protein molecules called actin and myosin, which help in the contraction function. Those little filaments are placed facing one another and they slide past each other during the contraction, which causes the muscle fibers to shorten. That is how the contraction and relaxation of a muscle occurs.

Peter, do you think that coincidence plays a role in this complex and wonderful mechanism and the incredible structure which I have attempted to simplify with an example? Not even a simple thread can be produced without a thread-maker or a machine. Each of your muscles comprises billions of fibers, wrapped all around your bones and giving shape to your body. Can such a complex and delicately intricate structure exist on its own and be positioned in the best place it could possibly be?

My muscles consist of bundles that are made of thousands of muscle fibrils; the size and shape of each muscle depends on which bone it is attached to and what function it does. For example, the muscles that move the bones in your arms and legs are long and spindle-shaped; whereas the ones that are attached to your body can be circular, or triangular, or spread over a broad area. Whatever shape they have, the red skeletal muscles, which are attached to your bones, are very strong and they are voluntary muscles, which mean you can control their movement. When you walk, run, do something with your hands, lie down or stand up, you always use my red striated muscles. The strias (stripes) can only be seen under a microscope because of the histological structure of these skeletal muscles that make up a great part of your body.

My smooth muscles are involuntary muscles that work without your control. Their movements are slow and their contractions last longer, which is the reason why they do not tire easily. The smooth muscles lie in the walls of digestive system, blood vessels, and urinary tract, but I will not talk much about them since each system has referred to the smooth muscles within itself and in detail in previous talks. Because they are not attached to your skeleton to work, the smooth muscles do not play a role in your movements, such as walking around; they only work for the movements of your inner organs.

The third type of muscle belongs to your heart (cardiac muscle) and although the heart has a little striated muscle tissue, it, too works involuntarily. Therefore, you should be aware of the fact that it is the striated muscles which work for the movement of the skeleton and do the major job, and that it is this that we refer to when we say “muscle.”

A great number of bones have been created in order to support your body, and joints have been placed between those bones for them to take the proper shape according to every movement. However, none of those joints have the ability to move by itself. A door or a window, no matter how good it is, cannot be opened or closed without an outside force to pull or push it. In the same way, a joint needs a force to move it and that force is produced by your muscular system. There are around 340 muscles included in your muscular system. It has been estimated that all the muscles in your body perform 510 different functions! While some of those functions are bone movements in your joints, other muscles can perform movements without moving a bone at all. Muscles that are placed in your forehead, face, eye lids and abdomen are those kinds of muscles. They can help you look worried by wrinkling your forehead or grimacing when you are disgusted by something.

Keeping with tradition, the muscles that are included in my system have been named based on the function they perform. For example, the muscle which moves an organ part towards another part is called an abductor, while the muscle that straightens a joint is an extensor, and the muscle that bends a joint is a flexor; the muscle that raises a part of the skeleton is a levator, that which the muscle makes a part of an organ prone is a pronator, the muscle that rotates a part of an organ is a rotator and that which brings an organ into a supine position is called a supinator.

In order for you to make all the movements that your body needs, my muscle components have to be both very strong and flexible. The most important feature of my muscle components is that they can be trained and strengthened with a systematic workout. The main goal of all sportsmen who compete is to increase the strength and the endurance of their muscles. As a result of intense exercises with weight and speed, the number, the diameter and the length of my muscle fibers will increase. Thus, I can gain more power to be able to do more work and also gain the ability to contract faster.

However, in addition to all this training and exercise, genetic factors also play a role in my health. For this reason, not everybody who works out can become a good sportsman; but if the person has innate muscular and skeletal capacity, with good exercise this capacity can certainly be enhanced and developed. However, if a person does not have the proper muscular structure for a particular sport, it would be unfair to expect them to be a champion! Although my muscles always seem to be of the same type at first sight, I might show different behavior depending on the distribution of the special fibers inside them. Some of my fibers twitch fast and tire easily, some of them twitch slowly and tire later. Depending on the distribution of these different fibers, the movements and sport that every person can do differ from person to person. In this case, an athlete who can run only 100m and an athlete who can run 10,000m do not have the same development of muscles; they have different amounts and distributions of special muscle fibers.

The contraction of any of my muscles can occur in two different ways: If the pressure put on my muscle is stronger than the resistance of the tissue, the tension remains constant and the muscle shortens. This is called an isotonic contraction. If the pressure put on my muscle is equal to the resistance, the tension of my muscle increases and its length does not change. That is called an isometric contraction. The amount of force that occurs during the contraction of my muscle depends on its length and the amount of the stimulus.

In order to produce muscle contraction, an electrical signal is sent through a motor neuron to the synaptic gap, which is positioned between the muscle cell membrane and the nerve cell. As a result, a chemical reaction occurs, which, in a very short time, causes the actin and myosin proteins in the muscle fibril to slide past each other and thus shorten the fibril, contracting the muscular cells. During this reaction, the temperature also rises a little and the total heat generated by all the muscles determines your body temperature. For this reason, in cold weather, my muscles vibrate, increasing your body temperature and trying to maintain it. You may now understand why moving the parts of the body in cold weather helps people avoid from getting sick or freezing. As you can see, every act of my Creator is quite purposeful. He can create two or even more functions within one task: Through your muscles, He not only provides you with the ability to move freely, but heat is also produced and you are protected from getting cold.

When a muscle fiber contracts frequently as a result of successive electrical impulses from a nerve fiber, it becomes tired after a while and needs rest. In this case, other muscle fibers which have not contracted for a while will take over and continue the job. However, if the electrical impulses from the nerve come too frequently and my muscle fibers do not have an opportunity to rest, a condition of constant contraction, which is known as physiologic tetanus, occurs.

The tension receptors that are placed on my muscles help maintain the harmony and coordination of all your movements including walking and running, bouncing and sitting down. They do this by constantly signaling the nerve system and providing feedback about the condition of my muscles, and about the speed and the intensity of contraction. Thus, through these receptors which control and coordinate my muscle activities, the well-being of my system is ensured. It is this that prevents you from wobbling when you walk, or helps you to take a spoonful of soup to your mouth without spilling it.

Like any other tissue or system, I, too, have some special disorders. The most common disorders are: weakness, malformation, muscles that develop and move involuntarily and habitually, especially in your face (tic), infected muscles (myosite), muscle dystrophy, muscle rigidity (the Stiffman Syndrome), benign or malignant muscle tumors (leiomyom, rhabdomyoma, or Rhabdomyosarcoma). These disorders differ in their degree of severity and risk.

Dear Peter! You have now seen that each muscle helps your organs to move, holding your bones and giving shape and function to your body, making you a beautiful model and an inspiration for sculptors. You may have understood that this is a work of knowledge and might; there is no way that the myofibril in my one cell could form by itself as a result of a coincidence.

Irfan Yilmaz is a professor of biology at Dokuz Eylul University, Izmir, Turkey.

Dancing in the enchantment of Your love,

Like a moth, the world is rushing to meet You,

I wish I could reach You, even if only once it may be.

I await, on the horizon of my hopes, the rise of the moon,

Your hands caressing my anguish-burned face,

You opened to me the sanctuary in Your presence,

May the torment of these painful days conclude soon.

My heart is hungry for Your eternal love,

My life-long palpitations will not ease otherwise,

Nor can my bosom sing in its finest voice.

Would my lips move without You in my heart?

Come and clear the face of my night of sorrow,

Make my troubled bosom happy with Your compliments,

Satisfy with Your love my endlessly searching soul,

Appear in my heart, declaring it Your home…

One recent example of such phenomena is the Schrödinger equation that explains the behavior of matter at the atomic level. This relation just happens to work, and its derivation is intuitive rather than rational. It also has the simplest mathematical form among its possible competitors in terms of expressing nature.

We will now look at another example of such axiom-like relations that we usually ignore, although it is frequently encountered in our everyday life. Before revealing it as fully as we can, let us relate one situation where this effect is very apparent.

We usually move objects by pushing or pulling them. Suppose now we are on a motorboat and we have run out of gas in a place very close to the shore. We (the strong crew members) surely do not want to be carried away from the shore by the backwash from the waves. One of us has the brilliant idea to push on the sides of the boat until we reach harbor. What would you suggest? Some of us think that it is not a good idea because the boat is very heavy and our pushing will be negligible. It is true that the boat will not move. However, the failure has nothing to do with the weight of the boat. On the other hand, some other crew members suggest using oars, which will obviously work, but why? (Personally, with all my respect to other opinions, I would suggest using the phone to call the beach police to get some help; but this would distract us from our subject matter.)

Impulse, direction, and momentum

If you think about the “why” question above, you will guess that we are talking about impulse in the loose meaning of the word. In physics, impulse has a more precise definition. This definition arose from the need to describe an object’s ability to have an impact on other objects, but the idea is still vague: How do we quantify this ability in order to put some flesh on this notion? Let us try to figure out an answer to this question.

Now, let us consider a few possible ways of defining impulse that look reasonable. We may decide intuitively that an impact should be related to an object’s speed: the higher the speed the greater the impact. If you ever played marbles in your childhood, you will recall that the easiest way to dislodge the marbles in the targeted row is to cast your own marble as fast as you can. Impulse should also have a relation to mass. Certainly, the impact of as many as a thousand bullets aimed at a train will not move the train even a meter. These are some simple observations anyone can experience or have a feeling of from their daily life.

We also expect that this strange quantity should somehow be transferred by the interaction of two objects. One object colliding with another stationary object transfers something that causes the latter to travel in a direction. With this example, another important feature of our impulse idea emerges: direction. Those who like to play the game of American pool or billiards know this very well. (I am sure everyone does it for the noble reason to experiment the laws of physics.) It makes a significant difference in a collision of two masses if they hit each other at an angle.

Wait a minute! We have been talking about the effect of an object’s impact, but the object has something that it is carrying even before the impact, and this “something” is the reason why we have an impact in the first place. So, what is this “something”? Let us call it momentum so as not to violate the traditions of physics.

All this stuff so far is good, but we are not done yet: how should these ideas appear in our equations? Now, let us bring together all our findings. We know momentum manifests itself as the impact (P) of one object on another. From its effect (impulse), we understand that momentum is related to the mass (M) of the object and its velocity (V). We also know that momentum has a directionality, which is termed vectorial. Then, perhaps momentum is something like:

P = a x M + b x V

where a and b are constants. This seems acceptable since it satisfies our observation: the more the mass, the more the momentum. But for a stationary object (V=0), there is no point in talking about impulse; so the axM terms looks unnecessary. If there is no good reason for a physical quantity to appear in a physical equation, then the simplicity principle says it should be removed. Therefore, we look for a simpler alternative relation with only one term like below:

P = c x M2 x V5

where c is a constant. But this one is a highly non-linear relation with exponential terms, so it is really not looking good. Another problem with this equation is that it does not fit our daily experience very well. If we reconsider our train example, with a high velocity power term like this, even the very small bullets can have a considerable effect on a train, enough to move it in fact. As a simple example, let c be equal to 1, take 0.1 kg as the mass of a bullet and 105 kg (100 tons) as the mass of the train, and give 400 m/s velocity to the bullet. Assuming that the impulse of the bullet is transferred to the train (conservation of momentum), we roughly get:

Pbullet = c x m2 x Vb5 = 1011

Ptrain = c x M2 x Vt5 = 1010 Vt5

By equating both sides we roughly get, 1.6 m/s (5.7 km/h) for the train velocity.

A single bullet moving a big train at such speed? This is a very counter-intuitive result. However, we will not give up easily. How about if we try an expression which is more familiar?

P = d x MV2

where d is a constant. This relation also agrees with our intuition (i.e. it has mass and velocity terms proportional to P.) I can already hear some objections from those who are acquainted with physics saying “No! This is the energy formula of a body with mass M and velocity V.” Indeed, this equation is reserved for energy which is a non-vectorial quantity. As a matter of fact, none of the above is a correct description for momentum. The actual expression is, interestingly, the simplest of all possibilities:

P = MxV

So, why not the more complex ones but this, the simplest one? The rigorous answer is subtle and requires a thorough analysis of linearity and homogeneity of space, which could be the subject of another essay. But we repeat the remark that we made in the beginning: if there is a simpler and more beautiful way of describing a natural law, then that description often turns out to be the correct one in the end. In fact, for some giants of physics like Paul Dirac, the beauty of a theory is more important than its results and is a better indication of the theory’s correctness. There is more to it than that. There are whole theories like Dimensional Analysis which are implicitly based on the idea of writing down the equations in the simplest (and most beautiful) form.

So, the final point is that, like other fundamental relations in physics, the idea of impact or momentum is best described in the simplest and most intuitive way: P= MxV. And behold! This gives us exactly the relation that has passed all the scientific tests in the range of classical physics. This result implies that the beauties we see in nature can be explained in terms of the simplest possible physical relation. Pondering all these, one cannot help but ask how in the world a mindless, blind natural law could exhibit beauty based on simplicity.

At the same time as these events are happening almost simultaneously, information from my eyes and my finger is being sent to the brain so that my finger will move in the way I expect it to. For example, if the path of my finger’s movement is somehow blocked, my brain can redirect it.

However, the event described above is not that simple. Starting from the neurons and continuing until we reach the muscles, every element that acts during this process displays extraordinarily complex alterations at both cellular and molecular levels.

Consider muscle cells, since they are moderately well understood. Upon arriving at the muscle cell, the electrical impulse causes the voltage-sensitive calcium channels in specific compartments within the cell to open and release calcium into the cell. You might remember from high school biology that muscle contraction is the result of two proteins (myosin and actin) sliding over each other. Normally, actins are masked by proteins known as tropomyosin. During the waiting period, therefore, the interaction between myosin and actin, which leads to contraction, cannot occur. This is why the muscle cell releases calcium, for when calcium is free in the cell, it binds to tropomyosin and enables it to move. As a result, actin is free to interact with myosin.1

After that, millions of molecules containing energy, known as ATP, bind to millions of myosin proteins, and the muscle contracts. When the contraction ends, the freed-up calcium is stored once again in specific compartments. When calcium is not present, tropomyosins again mask the actin proteins, and millions of muscle cells revert to their initial position, ready to respond to another contraction.

I realize that all of this is hard for the average reader to understand. However, the events that take place are even more complicated.

Expressions like “ATP binds to myosin” and “calcium is stored in compartments” are, in fact, simplified ways of explaining a highly complex event. Since there is a reason for everything, our cells should contain something that is performing these functions and carrying out such events. If we expand this problem to its limits, we will have to understand that each cell contains a large set of rapid and specific chemical reactions that occur constantly and yet do not interfere with one another. Based on current scientific knowledge, we can say that enzymes conduct almost all reactions in a cell, and that DNA has all the necessary information to produce enzymes. Enzymes are protein molecules that speed up and regulate all of the reactions that take place in a cell. If there were no enzymes, the reaction that a cell carries out in seconds could only be completed in thousands of years, and consequently, life as we know it would not exist. Life requires that the correct enzyme be found in the correct place and at the correct concentration.

Based on this, let’s revisit the above example. When the electric impulse reaches the muscle cell and calcium ions are released, this and every external and internal signal is conveyed to the DNA through a mechanism that we are just beginning to appreciate: signal transduction. Later, RNA is produced in those regions of the DNA that are responsible for producing the enzymes that enable the cell to give the appropriate answer (RNA helps DNA to produce enzymes). The synthesis of the enzyme is regulated at various checkpoints, such as during RNA production or RNA translocation out of the nucleus by other enzymes.2 ATPase, one of the many enzymes produced, makes it possible to use ATP, while another enzyme makes sure that the ATPases are in the correct location in the cell. Meanwhile, in order to sustain life, thousands of other enzymes conduct various reactions at the correct time and place. Therefore, when I move my finger, the number of active elements increases enormously.

Let’s look at the finer points of the cell. Using a simple calculation, in which each number is much smaller than the actual number used, if we assume that one million cells perform some kind of action from the reception of the first impulse in the brain until the time the muscle contracts, and if we calculate that one thousand reactions occur in each of these cells, this means that one billion reactions are performed for the simple action of moving a finger. One billion reactions, in just one second. And at the same time, my heart is beating, new blood cells are being produced, my eyes are sending visual information to my brain, my kidneys are filtering my blood, my lungs are exchanging old air with new, fresh air, my digestive system is supplying the necessary nutrients to my blood stream, and much, much more. Moreover, all of these are continually taking place. The fact that all of these actions are occurring, again based on a very rough and simple calculation, means that maybe one trillion reactions are occurring every second. As a result, a person might feel that it is quite possible, at any instant, for this perfect machine-the human body-to fall apart.

Realizing this, one might actually find it hard to believe that he or she is really alive. For example, I would never believe that such a machine would work if I did not have the empirical knowledge that it does work. How, for example, can I believe that I can produce one trillion reactions every moment and never confuse one with another, that it takes one billion reactions to move my finger, and that one trillion gears are working by themselves without making any mistakes?

With this idea in mind, I see the following lines in Epitomes of Light: “Also, since a building that contains every kind of artwork and riches cannot exist without having been built by someone, the existence of this universe is intimately connected with the existence of the Builder. If someone thinks carefully, it is impossible to accept one without the other.”3 Upon reading these words, I start to realize that all of these gears are not working by themselves, but rather that every second all of the trillion gears are being regulated by the One for whom nothing is difficult.

Suddenly, I remember that whenever the names of God are recited, I hear the name al-Hayy right next to al-Qayyum: God is He besides Whom there is no god; He is al-Hayy (the Ever-Living), al-Qayyum (the One Who sustains and protects all that exists) (Qur’an 2:255). Putting al-Qayyum next to “life” indicates, at least to me, that every living being is kept alive at each instant by al-Qayyum. If His control over each person’s existence were to be lost for even one second, one trillion gears would become irreversibly mixed up and the body would fall apart instantly. While thanking God for all that He has given me, I realize that I cannot thank Him enough for even one gear.

References

1. Harvey Lodish et al., Molecular Cell Biology, New York: Scientific American Books, c1995, 1027-29.
2. Lewin, Benjamin, Genes VI, Oxford, NY: Oxford University Press, 1997, 847.
3. Nursi, S., Epitomes of Light: Mathnawi al-Nuriya: The Essentials of the Risale-i Nur, Kaynak A.S., 1999.