Immortal Philosopher of Antiquity
384 - 322 B.C.
Born at Stagira in Macedonia (in northern Greece), the son of Nicomachus, Aristotle was together with Plato the most influential philosopher of the western tradition. At age 17 he entered Plato's Academy in Athens, and remained there until Plato's death.
Aristotle then accepted the invitation of Hermias to reside at Assos. Upon the death of Hermias (whose niece, Pythias, he married) in 345, Aristotle went to Mytilene on the island of Lesbos. Between 343/2 and 340 he acted as the tutor to the young Alexander the Great.
In 335 he returned to Athens where he founded a school, the Lyceum. Here he organized and conducted research on many subjects, and built the first great library of antiquity. After the death of Pythias he lived with Herpyllis, by whom he had a son, Nicomachus. On the death of Alexander in 325 anti-Macedonian feeling in Athens, caused Aristotle to retire to Chalcis where he died on the Aegean island of Euboea, now Ewoia in 322 B.C.
Inland from Stagira was the semi-Greek kingdom of Macedon, with which Aristotle's family was closely connected. Aristotle's father, for instance, had been court physician to the Macedonian king Amyntas II. Aristotle lost both parents while a child and was brought up by a friend of the family. He is supposed to have spoken with a lisp and to have been something of a dandy.
Of the two great philosophers of Greece, Plato and Aristotle, the latter was the one who relied on observation.
Raphael's The School of Athens shows the two great philosophers in the center of the painting, surrounded by the other great Greeks, with Plato holding his hand upright as if to indicate, "Look to the perfecti on of the heavens for truth," while Aristotle holds his arm straight out, implying "look around you at what is if you would know the truth."
We shall look deeper in Aristotle's ideas below.
At the age of 17 Aristotle traveled to Athens for a college education and after Plato returned from Syracuse, the young man joined Plato's Academy, where he studied assiduously. Eventually he was to become by far the most renowned of all the pupils of Plato. Plato called him "the intelligence of the school."
When Plato died in 347 B.C., Aristotle left the school.
In any case Aristotle found it expedient to set out upon a journey that carried him to various parts of the Greek world, particularly to Asia Minor. While there he married and engaged in the study of biology and natural history, always his chief love.
In 342 B.C. he was called to Macedon. The son of Amyntas II had succeeded to the throne of Macedon as Philip II while Aristotle was at the Academy, and now the king wanted the son of his father's physician back at court. The purpose was to install him as tutor for his fourteen-year-old son, Alexander the Great.
Aristotle held this position for several years. Since Alexander was to become Alexander the Great, the conqueror of Persia, we have the spectacle of the greatest soldier of ancient times being tutored by the greatest thinker.
In 336 B.C. Philip II was assassinated and his son succeeded as Alexander III. Alexander had no further time for education so Aristotle left Macedon the next year and went back to Athens while Alexander went on to invade the Persian Empire in a great conquering campaign. Aristotle's nephew, Callisthenes, accompanied Alexander, but Aristotle's influence over his erstwhile pupil was not very great for in 327 B.C. Callisthenes was executed by the increasingly megalomaniac monarch.
Meanwhile, in Athens, Aristotle founded a school of his own, the Lyceum, so called because Aristotle lectured in a hall near the temple to Apollo Lykaios (Apollo, the Wolf-God). It was also called the "peripatetic school" (walk about) because Aristotle, at least on occasion, lectured to students while walking in the school's garden. He also built up a collection of manuscripts a very early example of a "university library." It was this which eventually served as the kernel for the great Library at Alexandria.
The school continued under Aristotle's directorship quite successfully, emphasizing natural philosophy. In 323 B.C., however, the news arrived of the death of Alexander the Great in Babylon. Since Aristotle was well known to have been Alexander's tutor, he feared that an anti Macedonian reaction in Athens might lead to trouble. And, indeed, the accusation of "impiety" was raised. Aristotle had no mind to suffer the fate of Socrates. Saying he would not allow Athens to "sin twice against philosophy" he prudently retired to Chalcis, his mother's hometown, and died there the next year.
Aristotle's lectures were collected into nearly 150 volumes and represent almost a one-man encyclopedia of the knowledge of the times, much of it representing the original thought and observation of Aristotle himself. Nor was it confined entirely to science, for Aristotle dealt with politics, literary criticism, and ethics. Altogether, of the volumes attributed to him, some fifty have survived (not all of which are certainly authentic), a survival record second only to that of Plato. This survival came about through a fortunate chance. Many of his manuscripts were found in a pit in Asia Minor about 80 B.C. by men in the army of the Roman general Sulla. They were then brought to Rome and recopied.
The one field for which Aristotle is not noted is mathematics, but even here he may be credited with a glancing blow, for he is the virtual founder of the systematic study of logic, which is allied to mathematics. He developed, in great and satisfying detail, the art of reasoning from statement to necessary conclusion and thereby demonstrating the validity of a line of thought. His system stood without major change until the nineteenth-century development of symbolic logic by Boole, which converted logic in to a branch of mathematics in form as well as spirit.
Aristotle's most successful scientific writings were those on biology. He was a careful and meticulous observer who fascinated by the task of classifying animal species and arranging them into hierarchies. He dealt with over five hundred animal species in this way and dissected nearly fifty of them. His mode of classification was reasonable and, in some cases, strikingly modern. He was particularly interested in sea life and observed that the dolphin brought forth its young alive and nourished the fetus by means of a special organ called a placenta. No fish did this, but all mammals did, so Aristotle classed the dolphin with the beasts of the field rather than with the fish of the sea. His successors did not follow his lead, however, and it took two thousand years for biologists to catch up to Aristotle in this respect.
It was J. Muller who finally confirmed Aristotle in this respect. Aristotle also studied viviparous sharks, those that bear live young -- but without a mammalian placenta. He also noted the odd ability of the torpedo fish to stun its prey though, of course, he knew nothing of the electric shock with which it managed it. He was also wrong on occasion, as when he denied sexuality in plants. Nineteen centuries were to pass before Alpini was to correct this particular error.
His formation of a hierarchy of living things led him irresistibly toward the idea that animals represented a chain of progressive change, a sort of evolution. Other Greek philosophers groped similarly in this direction. However, barring any knowledge as to the physical mechanism whereby evolutionary changes could be brought about, such theories invariably became mystical. A rational theory of evolution had to await Darwin, 2200 years after the time of Aristotle.
Aristotle studied the developing embryo of the chick and the complex stomach of cattle. He decided that no animal had both tusks and horns, and that no single hoofed animal had horns. But his intuition sometimes led him astray. He believed the heart was the center of life and considered the brain merely a cooling organ for the blood.
In physics Aristotle was far less successful than in biology, perhaps because he was too Platonic. He accepted the heavenly spheres of Eudoxus and Callippus and even added further to them, reaching a total of 54. He seemed to think of the spheres as having an actual physical existence whereas Eudoxus probably thought of them as imaginary aids to calculation, as we consider the lines of latitude and longitude we draw on a map. Aristotle also accepted the four elements of Empedocles but restricted them to Earth itself. He suggested a fifth element "aether," of which all the heavens were composed. (We still use phrases such as "ethereal heights" today.)
This line of reasoning led him to agree with the Pythagoreans that Earth and heaven were subjected to two different sets of natural law. On Earth all things were changeable and corrupt, while in the heavens all was permanent and unchanging. On Earth the four elements each had its own place, and motion was an attempt to reach that place. Earth was in the center, water above it, air above that, and fire highest of all the earthly substances. Therefore an object composed largely of earth, such as a rock, would, if suspended in air, fall downward, while bubbles of air trapped under water would move upward. Again rain fell, but fire rose.
It also seemed to Aristotle that the heavier an object was, the more eagerly it would strive to achieve its proper place since the heaviness was the manifestation of its eagerness to return. Hence a heavier object would fall more rapidly than a lighter one. Nineteen centuries later, a reconsideration of this problem by Galileo was to lead to momentous consequences. The motion of heavenly objects, on the other hand, was no attempt to get anywhere. It was a steady, permanent motion, even and circular.
Aristotle, apparently, was not an experimentalist for all that he was a close observer. He observed that rocks fell more quickly than feathers, but he made no attempt to arrange an observation of the falling of rocks of graded weight. Furthermore, neither he nor any other ancient scholar properly appreciated the importance of precise, quantitative measurement. This was not mere perversity on their part, for the state of instrumentation was rudimentary indeed in ancient times and there were few clear methods of making accurate measurements. In particular, they could not measure small intervals of time accurately, a deficiency that was to remain for two thousand years until the time of Huygens.
Aristotle rejected Democritus' atomism, dooming that concept through ancient and medieval times. On the other hand, he accepted the Pythagorean notion of the roundness of Earth, presenting his reasoning in a fashion that remains valid today. The most telling argument was that as one travels north, new stars appear at the northern horizon while old ones disappear at the southern. If Earth were flat, all stars would be equally visible from all points on its surface. It was Aristotle's championing of this view that kept it alive through the darkest days that were to follow.
Aristotle's system of philosophy was never as influential in ancient times as Plato's. Indeed, Aristotle's works may not have been published for some centuries after his death. After the fall of Rome, his work was largely lost to Europe (only Organon, his work on logic, was saved) while Plato's works were, for the most part, retained. However, Aristotle's books survived among the Arabs, who valued them highly.
Christian Europe regained Aristotle from the Arabs, translating his books into Latin in the twelfth and thirteenth centuries. From that time Aristotle replaced Plato as the Philosopher. His views came to be regarded as possessing an almost divine authority, so that if Aristotle said it was so, it was so. By a queer fatality, it almost seemed as though his statements were most accepted when they were most incorrect.
This cannot be blamed on Aristotle, who was himself no believer in blind obedience to authority. Nevertheless, following the era of over-adulation, he became the very symbol of wrongness, and when the Scientific Revolution took place in the sixteenth and seventeenth centuries, its first victories involved the overthrow of Aristotelian physics. In the centuries since, Aristotle has, as a consequence, too often been viewed as an enemy of science, whereas actually he was one of the truly great scientists of all time and even his wrongness was rational. No man should be blamed for the stubborn orthodoxy of those who many centuries later insist they speak in his name.
The Greeks made a decisive choice in favor of the organismic viewpoint of nature. This choice was at least as Greek in spirit as the so-called of the Ionians. Some historians of science have tried desperately to present scientific rationalism as the only genuine exhibition of the Greek spirit. These historians have tried to support their case by claiming the influence of factors, such as religious ideas penetrating Hellas from the eastern shores of the Mediterranean, which were just as foreign to the Greek mind. In fact, long before religious ideas gained significant influence, the greatest of the Greek thinkers settled on the primacy of the organismic view, mainly because they found it to provide the type of intelligibility that best satisfied the aspirations of the Greek mind.
As Greek intellectual development after Plato continued through its phases, its formers, with great unanimity, adhered to organicism. Aristotle is very typical. A resolute critic of Plato's main philosophical construct, the theory of ideas, Aristotle remained nonetheless faithful to the basic tenet of the Socratic program: nature was to be understood as something like man himself -- moving toward goals, striving toward the best possible arrangement, in short, acting like an organism. He was convinced that the universe was supremely a living being both in its entirety and in its parts.
In fact, it is in Aristotle's Physics that one finds the first simultaneous occurrence of the terms microcosmos and megacosmos (macrocosmos), terms which were to serve as the characteristic stamp on every organismic theory about the universe until the very modern times. In the eighth book of the Physics, Aristotle reviewed several objections to a fundamental doctrine of his, the eternity of motion. According to these objections, motion need not always be caused by another motion but could at times be preceded by absolute rest. For proof, one of the arguments refers to the case of living beings, to human consciousness and animal behavior in particular.
...the animal...we say, moves itself; therefore, if an animal is ever in a state of rest, we have thing in which motion can be produced from the thing itself, and not from without. We see nothing like this in the case of inaminate things, which are always set in motion by something else from without: the animal, on the other hand, we say, moves itself; therefore, if an animal es ever in a state of abosolute rest, we have a motionless thing in which motion can be produced from the thing itself, and not from without. Now if this can occur in an animal, why should not the same be true also of the universe as a whole? If it can occur in a small world [microcosmos] it could also occur in a great one [megacosmos]...
The conclusions of this argument were totally contrary to the foundations of Aristotle's system. Nevertheless, all Aristotle found to criticize in this argument, was the conclusion alone and not the organismic analogy on which it rested. Aristotle offers no objection and finds no fault with the general organismic principle that allows one to move without any qualification from the small world of an animal to the large world of the inanimate universe. It was a principle that had to appear to him as basically sound. As a consequence, Aristotle, in general so reluctant to praise the intelligence of his opponents, qualifies the objection based on this principle as one he saw to "present more difficulty than the others" for his doctrine of the eternity of motion. Obviously he realized that the objection had carried the battle to his own grounds.
When faced with objections based manifestly on principles diametrically opposite to his own, Aristotle's phrases betrayed hardly any hesitancy or surprise. Thus in a highly revealing passage of the second book of the Physics Aristotle drew a sharp contrast between the early physics and what physics really ought to be. According to the former, nature does not work for the sake of something or because it is better one way than another; it rather works of necessity, that is, in a regularly repeated pattern of sequences. The necessity and regularity of his predecessors' physics had, however, been dependent on chance, and Aristotle eagerly seized on this obvious inconsistency. Chance, Aristotle argued, does not repeat things in a regular fashion. Regularity can be assigned only to purposeful action, which, as he contended, always works for an end and originates from the particular nature that is acting. It was at this point that Aristotle reaffirmed the basic goal of Socrates' arguments: the restoration of unity between man and nature in an organic whole. The declaration of a perfect parallelism between the way man acts and the manner in which nature operates could not be more explicit:
As in human operations, so in natural processes; and as in processes, so in human operations (unless someting interferes). Human operations are for an end, hence natural processes are so too.". .
To Aristotle, the "physical method," as he referred to Democritus' approach to nature (mechanism), failed in this most essential aspect because it tried to explain things and processes by decomposing them into their parts leaving aside the aspect of their wholeness. But, as Aristotle insisted time and again, basic information about objects, living and nonliving alike, could be obtained only by a method that concentrated on the wholeness in things and processes. Whether an animal or a couch is to be explained, the investigation should take its start from a definition of the whole, a definition that will shed light on the role of organs or parts played in the whole.
For it is not enough to say what are the stuffs out of which an animal is formed, to state, for instance, that it is made of fire or earth -- if we were discussing a couch or the like, we should try to determine its form rather than its matter (e.g. bronze or wood), or if not, we should give the matter of the whole. ... For the formal nature is of greater importance than the material nature...
By stressing the priority of the whole over the parts instead of treating the whole merely as a sum of the parts, Aristotle meant, in fact, that
For the formal nature is of greater importance than the material nature...
Or, in other words, the study of nature is to be dominated by the idea expressing the coordination of parts in the whole, which is the principle of organism. Believing that animate and inanimate beings alike have coordinated parts, Aristotle lowered the dividing wall between the two domains to such an extent that comparisons between the living and non-living became the most naturally used device in his writings on natural science. Speaking of the merits of the study of animals, Aristotle was highly elated about the teleology displayed in the animal world and concluded:
...the true object of architecture is not bricks, mortar, or timber, but the house; and so the principal object of natural philosophy is not the material elements, but their composition, and the totality of the substance, independently of which they have no existence...
Although modern natural science is reluctant to speak in the same breath of bricks and animals, Aristotle saw a basic justification for doing so in the wholeness allegedly present in any object. Of this holistic approach to the study of nature Aristotle stated in the most categorical terms that it is precisely there that the "physical" method and the "true" investigation of nature part ways. When refuting the opinions of Anaximenes, Anaxagoras, and Democritus on the flatness and motion of Earth, Aristotle tells us
In general, our quarrel with those who speak of movements in this way cannot be confined to the parts; it concerns the whole universe...
Once the wholeness of an object is grasped, said Aristotle, its properties and parts will readily reveal themselves. The golden key to the wholeness or nature of a thing consists in detecting its spontaneous motion. Implicit in this spontaneity is the goal of the motion, which in turn lays bare the nature of the thing in motion.
All the things mentioned [things that exist by nature] plainly differ from things which are not constituted by nature. For each of them has within itself a principle of motion and of stationariness (in respect place, or of growth and decrease, or by way of alteration).7
As opposed to products of crafts, the beings "constituted" or formed by nature, animals, plants, earth, fire, air, and water have within themselves the beginning of movement:
All natural bodies and magnitudes we hold to be, as such, capable of locomotion; for nature, we say, is their principle of movement.8
Formed by nature they move toward their respective ends, and the end of such a natural motion is identical with the purpose for which the thing exists.
...whenever there is plainly some final end, to which a motion tends should nothing stand in the way, we always say that the one is for the sake of the other...
Motion, nature, organism, and teleology, therefore, were simply different aspects of one basic viewpoint, in which locomotion, qualitative change, the growth of the living, and the healing of the sick were treated on the same footing. Having rejected the possibility of a regress to infinity, Aristotle thought he could readily show that if there is anything at all to exist, its motion, the primordial motion, should be a natural one. On the other hand, if the first motion
was natural, careful consideration will show that there was already a world.
This statement, directed against the notion of atoms whirling in space in every direction before the present configuration of things came to take shape, should forcefully intimate the multitude and sweep of conclusions that Aristotle derived from the concept of natural motion. After all, his universe was a "huge nature" of which all parts were moving, striving, and yearning toward their respective ends.
In fact, Aristotle needed only the distinction between the two types of natural motion, circular and straight, to be ready to tell us what it is like to be a cosmos.
First, the nature of circular motion proved for him that the cosmos must be finite.
Second, this finite universe is divided into two distinct regions, the upper part, or the region of celestial spheres, where the circular motion reigns supreme, and the region interior to the orbit of the moon (subluminary) filled with ordinary matter whose nature is to move up or down.
Third, since motion reveals the nature or substance of things, the celestial spheres and bodies, stars and planets, must be composed of a material as different from ordinary matter, as circular motion is from rectilinear. The ether, as this heavenly substance is called, is therefore a material whose nature is to issue in a uniform circular motion.
Fourth, it also follows from the Aristotelian analysis of uniform circular motion that the ether is unalterable, suffers neither growth nor diminution, and has no beginning or end, which is to say that it can be neither generated nor corrupted.
Fifth, to show that only one such substance can exist in the universe, Aristotle drew on the concept of nature and purpose and declared that a second substance of this type would be as pointless as "a shoe is pointless when it is not worn. But God and Nature create nothing that is pointless."
Aristotle's wizardry in squeezing out a long list of conclusions from one basic proposition is astonishing but hardly convincing. He presents his argument that the primary body, or ether, cannot be infinitely extended in no less than six variations. The great effort expended was superfluous, however, for as it turned out, the "nature" of any of the four elements could provide for Aristotle a specious argument against the infinity of the universe. Characteristically, according to him, one of the reasons for discarding the concept of an infinite number of atoms moving in infinite space was that in infinite space no natural motion can take place, because in infinite space no place or point can be assigned unambiguously as the endpoint of any object's motion.
Since the nature of a body determines the pattern or the direction of its motion, it follows that all Earth would move of itself toward the same place, which is the center of the universe, and all fire would always move upward toward the circumference of the world. The weighty problem of the multiplicity of worlds is thereby readily "solved" in a reasoning, the parts of which are as tightly interlocking as the parts of any organism:
For either we must refuse to admit the identical nature of the simple bodies in the various universes, or, admitting this, we must make the center and the extremity one as suggested. This being so, it follows that there cannot be more worlds than one.
Aristotle took pains to emphasize that distances between worlds, however large, could change the nature of things and their natural orientations. In other words quantitative considerations cannot negate the conclusions derived from the analysis of the behavior of an organism. Now if the world is an immense but finite and unique organism, it is only natural that all matter available in the universe should be coordinated to that "one, and unique, and complete" system,13 or else nature would have produced something to no purpose, which is unacceptable. Therefore no places, nor void, nor time exist beyond the limits of the universe, for the existence of any one of these would presuppose the existence of a natural body distinct from the unique cosmos.
The concept of "nature" secures for the world not only its uniqueness and finiteness, but also a life of perfection. The highest degree of life in the cosmos resides in the sphere of the ether:
...this motion, being perfect, contains those imperfect motions which have a limit and a cessation, having itself no beginning or end, but unceasing through the infinity of time. ... Further, it is unaffected by any mortal discomfort, and, in addition, effortless...
as should be with a uniform circular motion. But for life to be perfect, it must contain whatever "is present in the lowest stage of animal life." Therefore, like animals, the heavens must have front and back, left and right, above and below. The three-dimensionality of space is, in fact, just a corollary of the motion of living bodies, that is, bodies that have the principle of motion in themselves. The vertical direction is a consequence of growth that is from above, and the two horizontal directions are the results of locomotion that is from right to left (the right being the more noble side) and of the sensations that are from the front. Now since
the heaven is animate and possesses a principle of movement, clearly the heaven must also exhibit above and below, right and left. ... We must think of the world as of something in which right differs from left in shape as well as in other respects, which subsequently is included in a sphere.
The direction of the revolution of the skies shows, therefore, that the celestial hemisphere seen in the northern latitudes is really the lower half of the universe, the southern pole of the skies being the top of the cosmos. Hence, those who live in the southern regions are
in the upper hemisphere and to the right, while we are in the lower and to the left.
An absolutely valid coordinate system is indeed one of the consequences of viewing the world an as organism. What is more, the three perpendicular directions, being corollaries of life and motion, are not even of the same "dignity." The vertical direction is the most important, since the growth that manifests it can be found in every living thing, whereas the horizontal directions are of lesser rank because they cannot be discerned as basic direction of motion or growth in every living thing, such as a plant.
In the Aristotelian system the world taken as an organism revealed its features with alarming ease once its basic striving or nature had been defined. With a tour de force almost unparalleled in the history of science Aristotle showed in a single breath-taking page of On the Heavens, why the world should consist of different parts and why these parts should be the very same parts we actually observe in the world.
His seductive, a priori account of the main features of the universe reveals in its true nature the liberties that an organismic type of physics unavoidably takes in its approach to nature. Some details are especially worth considering if one is to obtain a close-up view of the dubious procedures that physical science is forced to adopt when the universe is viewed as an organism and when motion is believed to unravel the nature of things with dazzling ease. Thus Aristotle declared that the outermost shell of the cosmos is by necessity spherical, for it is made of divine substance and whatever is divine must be circular. It must also be perfectly smooth, for otherwise there would be "places" beyond the limiting circle and that would be tantamount to a contradiction in terms.
The direction of the revolution of the heavens is not haphazard either, because "... nothing which concerns the eternal can be a matter of chance or spontaneity..." In other words the actual direction of this revolution should be accepted as a right to left movement, for right is superior to left. But can the fact be an explanation of the fact itself? Very much so, runs Aristotle's answer, "Supposing that nature is ordered in the best way possible, this may stand as the reason of the fact mentioned."
The invariable speed of the heavenly revolution too is but an aspect of its eternal nature. Since a decrease of speed is a loss of power, Aristotle argued that such a loss could not take place in the heavens composed of the ether, a substance which by definition was not subject to decay of any sort. On a similar basis is decided the question of the composition of the stars too. If there is a body whose nature is to move in a circle, it is only logical to suppose, the argument runs, that the stars, which have a circular motion, are made of that substance, which again by definition is the ether. On such ground one can also readily discern, so Aristotle believed, whether the stars move round the heavens in the manner of progression observable in living beings. To resolve this question so strongly conditioned by the organismic approach, Aristotle, of course, had to resort to organismic analogies to clinch his proof.
If the stars moved in such a way, he argued, nature would have provided them with organs of motion closely resembling those of the animals. But nature, which provides so generously for even the lower types of being, seems to have made the stars as different as possible from creatures that are endowed with various organs of motion. Thus the stars are spherical because a sphere, which is best suited for motion in the same place, is the least suited to progression
For while of all shapes the sphere is the most convenient for movement in one place, making possible, as it does, the swiftest and most self-contained motion, for forward movement it is the most unsuitable least of all resembling shapes which are self-moved, in that it has no dependent or projecting part, as a rectilinear figure has, and is in fact as far as possible removed in shape from ambulatory bodies.
Not every motion in the heavens, however, has the apparent simplicity and uniformity of the stars. It was in fact impossible to avoid facing the question of fitting the complicated motion of planets into the divine simplicity of the heavens. In an organismic explanation of the world this gravest of all questions that ancient astronomers grappled with presents no difficulty at all. Aristotle warned:
We think of the stars as mere bodies and as units with a serial order indeed but entirely inanimate; but we should rather conceive them as enjoying life and action. On this view the facts cease to appear surprising.
Thus Aristotle, to explain the irregularities of planetary motions, fell back on one of his stock illustrative examples: the various phases in the progress of a sick organism toward health. The closer one is to health, goes the narrative, the fewer steps are needed to reach it. One individual may be healthy without any exercise, another may need only a little walking, a third might have to exercise strenuously, and a fourth may simply never become healthy despite tremendous exertions. Now, since the case of planets is taken without any second thought to be analogous to that of animals and plants striving for health, it is easy to see, contended Aristotle, that the farther a planet is from the sphere of the stars, the region of perfect life, the more cumbersome would be its motion. Clearly, if difficult problems could be solved with such ease, one could hardly feel doubt about the merits of the solution.
However, one must admit that Aristotle was extremely consistent in claiming that the errors of his predecessors on Earth's immobility, place, and shape were due to their ignorance of the concept of natural motion. In other words, he took them to task for not approaching the problems of geophysics from an organismic viewpoint. This was particularly true of the Pythagoreans, who preferred mathematical notions and geometrical patterns to organismic analogies. For them Earth was revolving around the central fire, the function of which was, in their belief, to protect the most noble part of the cosmos: its geometrical center. But Aristotle quickly retorted that
... it is better to conceive of the cae of the whole heaven as analogous to that of animals, in which the center [or heart] of the animal and that of the body are different.
Therefore he concluded on a markedly triumphant note that it is not the mathematical center of the world that should hold the place of honor, but rather its true center. Where this true center might be, however, can be established in the framework of an organismic physics only through an analysis based on the natural motion of bodies. On such grounds, an abstract geometrical point obviously could not compete with the massive body of Earth for the central position in the universe. For could an abstract point display "strivings" and "affections," those supreme signs of intelligibility?
The same attitude, emphasizing invariably the primacy of organismic concepts and their primordial intelligibility, dominated Aristotle's refutation of the geophysical views of the other pre-Socratic philosophers. Aristotle claimed that those who like Thales let Earth rest on water evidently did not understand the nature of water, which is not supposed to carry any heavier body such as Earth. Those who stated that a huge vortex keeps Earth in the middle failed to see, he remarked, that if there is a motion by constraint, there should be a prior natural motion. Those who invoked the principle of indifference to account for the immobility of Earth did not fare much better in Aristotle's eyes. They reasoned that an object situated at the center and related equally to the extremes in every direction can have no impulse to move in any specific direction. In fact, they compared the situation of such an object with that of a man violently but equally hungry and thirsty, standing at the same distance from food and drink and unable to decide in which direction to move.
Aristotle, however, rejected this apparently so "organismic" reasoning on the ground that it is not organismic enough. A consistently organismic explanation, he warned, cannot ignore the basic strivings of all types of matter. True, he admitted, a heavy body, such as stone, has such a completely natural indifference to moving toward the periphery. Such is not the case, however, with the light bodies, air and fire, which show an innate tendency to move toward the periphery of the universe, all whose parts are equidistant from Earth. Therefore, concluded Aristotle, Earth's rest at the center of the universe should be taken as a consequence of Earth's nature and not of its position there.
Aristotle could not leave this subject without making a remark that brings out vividly how the intuitive, all-embracing "intelligibility" of the organismic approach can deprive science of the best source of understanding, the benefits of judicious observation. One condition for making such an observation is clearly one's ability to concentrate his attention on the thing or phenomenon to be observed -- in other words, to isolate it from anything merely accidental or circumstantial. The organismic approach to nature has no patience with such a methodical isolation of inanimate things from their surroundings and from one another.
For as long as the concept of organism reigns supreme in physical science, things in nature are viewed as organically interconnected, and the notion of an isolated part becomes basically deficient. His opponents, Aristotle claimed, kept considering only isolated aspects of an organic whole and this he found an inadmissible procedure.