THE  ATOMISTS: LEUCIPPUS AND DEMOCRITUS

 

Leucippus of Abdera (or Miletus, or Elea) and Democritus of Abdera, the latter, according to his own statement, forty years younger than Anaxagoras, were the founders of the Atomistic philosophy. These philosophers posit, as principles of things, the "full" and the "void," which they identify respectively with being and non-being or something and nothing, the latter, as well as the former, having existence.

They characterize the "full" more particularly, as consisting of indivisible, primitive particles of matter, or atoms, which are distinguished from one another, not by their intrinsic qualities, but only geometrically, by their form, position, and arrangement. Fire and the soul are composed of round atoms. Sensation is due to material images, which come from objects and reach the soul through the senses.  The ethical end of man is happiness, which is attained through justice and culture.

 

Of the age of Leucippus and the circumstances of his life little is definitely known; it is also uncertain whether he wrote anything himself, or whether Aristotle and others drew their information concerning his opinions from the writings of his pupil Democritus. Aristotle commonly names him in connection with Democritus. The statement that he heard Zeno, the Eleatic, receives confirmation from the character of his doctrine. That the principles of his philosophy were largely derived from the Eleatics is also testified by Aristotle.

Democritus of Abdera, said that he wrote his work 730 years after the capture of Troy, and that he was forty years younger than Anaxagoras. He must, according to the latter statement, have been born about 460 BC, with which date agrees the statement of Apollodorus; according to Thrasyllus in 470 BC; but for tho date of the capture of Troy Democritus appears to have assumed, instead of 1184, the year 1150, whence we derive, as the date of the composition of the work named, the year 420 BC. He is said to have died at a great age (ninety years old; according to others, one hundred, or even more). Desire for knowledge led him to undertake extended journeys, Egypt and the Orient being among the places visited by him. Plato never mentions him, and speaks only with contempt of the materialistic doctrine. Plato desired, according to tho narrative of Aristoxenus the Aristotelian, that the writings of Democritus should be burned, but was convinced by the Pythagoreans Amyelas and Clinias, of the uselessness of such a proceeding, since tho books were already widely circulated. Aristotle speaks of Democritus with respect.

Democritus wrote numerous works. His style is greatly praised by Cicero, Plutarch, and Dionysius, for its clearness and elevation.

The Atomistic system was urged by Democritus, who perfected il and raised it to an acknowledged position, in opposition to ths Anaxagorean. The relation between Leucippus and Anaxagoras is uncertain. Since Democritus is called by Aristotle an intimate companion and disciple of Leucippus, the difference between their ages can hardly have amounted to forty years, so that Leucippus must have been younger than Anaxagoras.

If Anaxagoras did not make himself known by his philosophical productions in early life, it may be that Leucippus (who appears to bo immediately associated with the doctrine of Parmenides by his polemic against it) preceded him in this respect; yet this is not very probable, and can by no means be concluded from certain passages of Anaxagoras, in which he combats opinions (in particular the hypothesis  of empty interatomic spaces) that are, it is true, found in the writings of the Atomists, but had already been propounded by earlier philosophers (especially by Pythagoreans), and had also been, in part, combated by Parmenides and Empedocles. In view of this uncertainty respecting Leucippus and of the undoubted reference which Democritus constantly makes to Anaxagoras, we place the exposition of the Atomistic system immediately after that of the Anaxagorean. Besides, the nature of the doctrine of Homoemeriae, which is a sort of qualitative Atomism, places it in the middle between the four qualitatively different elements of Empedocles and the reduction by Leucippus and Democritus of all apparent qualitative diversity to the merely formal diversity of an infinite number of atoms.

In his account of the principles of the earlier philosophers, in the first book of the Metaphysics, Aristotle says: "Leucippus and his associate, Democritus, assume as elements the full and the void. The former they term being, the latter, non-being; hence they assert, further, that non-being exists as well as being". According to another account, Democritus expressed himself thus:

"Thing is not more real than nothing.

The number of things in being (atoms) is infinitely great.

Each of them is indivisible.

Between them is empty space".

In support of the doctrine of empty space, Democritus alleged, according to Aristotle, the following grounds:

1. Motion requires a vacuum; for that which is full can receive nothing else into itself;

2. Rarefaction and condensation are impossible without the existence of empty intervals of space;

3. Organic growth depends on the penetration of nutriment into the vacant spaces of bodies;

4. The amount of water which can be poured into a vessel filled with ashes, although less thau the vessel would contain if empty, is not just so much less as the space amounts to, which is taken up by the ashes; hence the one must in part enter into the vacant interstices of the other.

The atoms differ in the three particulars of shape, order, and position. As an example of difference in shape, Aristotle cites the Greek characters A and N, of order or sequence AN and NA, and ol the difference of position Z and N. As being essentially characterized by their shape, Democritus seems to have called the atoms also ideas. These differences are sufficient, according to the Atomists, to explain the whole circle of phenomena; are not the same letters employed in the composition of a tragedy and a comedy? The magnitude of the atoms is diverse. The weight of each atom corresponds with its magnitude.

The cause of the atoms is not to be asked after, for they are eternal, and hence uncaused. (It was probably not the Atomists themselves, but later philosophers, who first hypostasized this very absence of a cause iuto a species of cause or efficient nature).

Democritus is said also to have declared the motion of the atoms to be primordial and eternal. But with this statement we find united the other, that the weight of the larger atoms urged them downward more rapidly than the others, by which means the smaller and lighter ones were forced upward, while through their collision with the descending atoms lateral movements were also produced. In this way arose a rotatory motion, which, extending farther and farther, occasioned the formation of worlds. In this process homogeneous elements came together (not in consequence of the agency of ''love" and ''hate," or an all-ruling "Mind," but) in obedience to natural necessity, in virtue of which things of like weight and shape must come to the same places, just as we observe in the winnowing of grain. Many atoms having become permanently united in tho course of their revolutions, larger composite bodies and wholo worlds came into existence.

Tho earthwas originally in motion, and continued thus, while it was yet small and light; but gradually it came to rest. Organized beings arose from the moist earth. The soul consists of fine, smooth, and round atoms, which are also atoms of fire. Such atoms are distributed throughout the whole body, but in particular organs they exercise particular functions. The brain is the seat of thought, the heart, of anger, the liver, of desire. When we draw in the breath we inhale soul-atoms from the air; in the expiration of breath we exhale such atoms into the air, and life lasts as long as this double process ia continued.

Sensuous perception is explained by effluxes of atoms from the things perceived, whereby images are produced, which strike our senses. Through such effluxes, says Democritus, even the gods manifest themselves to us. Perception is not wholly veracious; it transforms the impressions received. The atoms are invisible on account of their smallness (only excepting, perhaps, those which come from the sun). Atoms and vacuity are all that exists in reality; qualitative differences exist only for us, in the sensuous phenomenon.

The assertion of Democritus, that in reality we know nothing, etc., must, as employed by him, probably be restricted to the case of sensuous phenomena; for in view of the assurance with which Democritus professes tho doctrine of atoms, this skeptical utterance can not be supposed to bear upon that doctrine itself. Democritus also expressly distinguished from sensuous perception, which he called obscure knowledge, the genuine knowledge acquired by the understanding through investigation.

That kind of philosophical thinking by which Democritus went beyond the results of sensuous perception and recognized in the atoms the reality of things, was not made by him itself a subject of philosophical reflection, and the manner in which such thinking is effected was left by him without special explanation; it is among the philosophers of the following period (with the earliest among whom Democritus was indeed contemporaneous) that reflection concerning the nature of thought itself begins. Yet it follows from the fundamental principles of Democritus that thought can not be independont of sensation. The only expression which Democritus appears to have given to his views concerning the origin of true knowledge, is that implied in the principle which he enounced in agreement with Anaxagoras, that we should proceed in our inferences from phenomena to the unknown, and in his doctrine that thought arises when the motions of the soul are "symmetrical" .

The soul is the noblest part of man; he who loves its goods, loves what is most divine. He who loves the goods of the body, which is the tent of the soul, loves the merely human. The highest good is happiness. This is attained by avoiding extremes and observing the limits fixed by nature. Not external goods secure happiness; its seat is the soul. Not the act as such, but the will, determines moral character. The highest satisfaction comes from  knowledge. The country of the wise and good is the whole world.

In the ethical theorems of Democritus, as also in those which relate to the difference between objective reality and our subjective apprehension of it, and which belong to the theory of cognition, the tendency to overstep the limits of cosmology becomes manifest—a tendency not wanting to any of the older philosophers and peculiarly natural in those standing on the borders of the first period. Democritus, the contemporary of Socrates, but younger than he, went considerably farther in this direction than Anaxagorus or any other of the earlier thinkers.

The first disciples and successors of Democritus (among whom Metrodorus of Chios is the most important) seem to have emphasized more strongly and developed to a greater extent the skeptical elements, which were contained more particularly in his doctrine of sensuous perception.