In time, he would become one of the most famous of the pre-Socratic philosophers. Leucippus of Miletus had the greatest influence on him, becoming his mentor and sharing his theory of atomism with him.
Democritus is also said to have known Anaxagoras, Hippocrates and even Socrates himself though this remains unproven. During his time in Egypt, he learned from Egyptian mathematicians, and is said to have become acquainted with the Chaldean magi in Assyria. In the tradition of the atomists, Democritus was a thoroughgoing materialists who viewed the world in terms of natural laws and causes.
This differentiated him from other Greek philosophers like Plato and Aristotle, for whom philosophy was more teleological in nature — i.
According to the many descriptions and anecdotes about Democritus, he was known for his modesty, simplicity, and commitment to his studies. One story claims he blinded himself on purpose in order to be less distracted by worldly affairs which is believed to be apocryphal. Democritus is renowned for being a pioneer of mathematics and geometry.
He was among the first Greek philosophers to observe that a c one or pyramid has one-third the volume of a cylinder or prism with the same base and height. While none of his works on the subject survived the Middle Ages, his mathematical proofs are derived from other works with contain extensive citations to titles like On Numbers, On Geometrics, On Tangencies , On Mapping , and On Irrationals. Democritus is also known for having spent much of his life experimenting with and examining plants and minerals.
Similar to his work in mathematics and geometry, citations from existing works are used to infer the existence of works on the subject. From his examination of nature, Democritus developed what could be considered some of the first anthropological theories.
According to him, human beings lived short lives in archaic times, forced to forage like animals until fear of wild animals then drove them into communities. He theorized that such humans had no language, and only developed it through the need to articulate thoughts and ideas. Through a process of trial and error, human beings developed not only verbal language, but also symbols with which to communicate i. Later atomists cite as evidence for this the gradual erosion of bodies over time.
These films of atoms shrink and expand; only those that shrink sufficiently can enter the eye. It is the impact of these on our sense organs that enables us to perceive. Visible properties of macroscopic objects, like their size and shape, are conveyed to us by these films, which tend to be distorted as they pass through greater distances in the air, since they are subject to more collisions with air atoms.
The properties perceived by other senses are also conveyed by contact of some kind. Democritus' theory of taste, for example, shows how different taste sensations are regularly produced by contact with different shapes of atoms: some atoms are jagged and tear the tongue, creating bitter sensations, or are smooth and thus roll easily over the tongue, causing sensations of sweetness. Theophrastus, who gives us the most thorough report of Democritus' theory, criticizes it for raising the expectation that the same kinds of atoms would always cause similar appearances.
However, it may be that most explanations are directed towards the normal case of a typical observer, and that a different account is given as to the perceptions of a nontypical observer, such as someone who is ill.
Democritus' account why honey sometimes tastes bitter to people who are ill depends on two factors, neither of which undercut the notion that certain atomic shapes regularly affect us in a given way.
One is that a given substance like honey is not quite homogeneous, but contains atoms of different shapes. While it takes its normal character from the predominant type of atom present, there are other atom-types present within.
The other is that our sense-organs need to be suitably harmonized to admit a given atom-type, and the disposition of our passageways can be affected by illness or other conditions. Thus someone who is ill may become unusually receptive to an atom-type that is only a small part of honey's overall constitution. Other observed effects, however, require a theory whereby the same atoms can produce different effects without supposing that the observer has changed.
The change must then occur in the object seen. Aristotle gives this as the reason why color is not ascribed to the atoms themselves. Lucretius' account of why color cannot belong to atoms may help clarify the point here. We are told that if the sea's atoms were really blue, they could not undergo some change and look white DRN 2. This seems to assume that, while an appearance of a property P can be produced by something that is neither P nor not-P, nonetheless something P cannot appear not-P.
Since atoms do not change their intrinsic properties, it seems that change in a relational property, such as the relative position of atoms, is most likely to be the cause of differing perceptions. In the shifting surface of the sea or the flutter of the pigeon with its irridescent neck, it is evident that the parts of the object are moving and shifting in their positional relations. By ascribing the causes of sensible qualities to relational properties of atoms, Democritus forfeits the prima facie plausibility of claiming that things seem P because they are P.
Much of Theophrastus' report seems to focus on the need to make it plausible that a composite can produce an appearance of properties it does not have. Democritus is flying in the face of at least one strand of commonsense when he claims that textures produce the appearance of hot or cold, impacts cause colour sensations.
The lists of examples offered, drawing on commonsense associations or anecdotal experience, are attempts to make such claims persuasive. Heat is said to be caused by spherical atoms, because these move freely: the commonsense association of quick movement with heating is employed. The jagged atoms associated with bitter taste are also said to be heat-producing: there, the association of heat with friction is invoked.
It is not so much the specific intrinsic qualities—smooth or jagged shape—as the motion of those shapes that provides the explanation. Aristotle sometimes criticizes Democritus for claiming that visible, audible, olfactory and gustatory sensations are all caused by touch DK 68A Quite how this affects the account of perception is not clear, as the sources tells us little about how touch is thought to work. Democritus does not, however, seem to distinguish between touch and contact, and may take it to be unproblematic that bodies communicate their size, shape and surface texture by physical impact.
According to Aristotle, Democritus regarded the soul as composed of one kind of atom, in particular fire atoms. This seems to have been because of the association of life with heat, and because spherical fire atoms are readily mobile, and the soul is regarded as causing motion. Democritus seems to have considered thought to be caused by physical movements of atoms also.
This is sometimes taken as evidence that Democritus denied the survival of a personal soul after death, although the reports are not univocal on this. One difficulty faced by materialist theories of living things is to account for the existence and regular reproduction of functionally adapted forms in the natural world.
Although the atomists have considerable success in making it plausible that a simple ontology of atoms and void, with the minimal properties of the former, can account for a wide variety of differences in the objects in the perceptible world, and also that a number of apparently orderly effects can be produced as a byproduct of disorderly atomic collisions, the kind of functional organization found in organisms is much harder to explain. Democritus seems to have developed a view of reproduction according to which all parts of the body contribute to the seed from which the new animal grows, and that both parents contribute seed DK 68A; The theory seems to presuppose that the presence of some material from each organ in the seed accounts for the development of that organ in the new organism.
Parental characteristics are inherited when the contribution of one or other parent predominates in supplying the appropriate part. The offspring is male or female according to which of the two seeds predominates in contributing material from the genitals.
In an atomist cosmos, the existence of particular species is not considered to be eternal. Like some other early materialist accounts, Democritus held that human beings arose from the earth DK 68A , although the reports give little detail. One report credits Democritus and Leucippus with the view that thought as well as sensation are caused by images impinging on the body from outside, and that thought as much as perception depends on images DK 67A Thought as well as perception are described as changes in the body.
Democritus apparently recognized that his view gives rise to an epistemological problem: it takes our knowledge of the world to be derived from our sense experience, but the senses themselves not to be in direct contact with the nature of things, thus leaving room for omission or error.
A famous fragment may be responding to such a skeptical line of thought by accusing the mind of overthrowing the senses, though those are its only access to the truth DK68B Other passages talk of a gap between what we can perceive and what really exists DK 68B6—10; But the fact that atoms are not perceptible means that our knowledge of their properties is always based on analogy from the things of the visible world. Moreover, the senses report properties that the atoms don't really possess, like colors and tastes.
Thus the potential for doubt about our knowledge of the external world looms large. Therefore, changes in matter were a result of dissociations or combinations of the atoms as they moved throughout the void.
Although Democritus' theory was remarkable, it was rejected by Aristotle, one of the most influential philosophers of Ancient Greece; and the atomic theory was ignored for nearly 2, years. Since Aristotle was such an influential philosopher, very few people disagreed with him. However, there were some philosophers who believed that there was a limit to how small a grain of sand could be divided.
One of these philosophers was Democritus c. He taught that there were substances called atoms and that these atoms made up all material things. The atoms were unchangeable, indestructible, and always existed.
There was an infinite number of atoms, but different types of atoms had different sizes and shapes. The void was the empty space in which the atoms moved and collided with one another.
When these atoms collided with one another, they might repel each other or they might connect in clusters, held together by tiny hooks and barbs on the surface of the atoms. Aristotle disagreed with Democritus and offered his own idea of the composition of matter. According to Aristotle, everything was composed of four elements: earth, air, fire, and water.
The theory of Democritus explained things better, but Aristotle was more influential, so his ideas prevailed. We had to wait almost two thousand years before scientists came around to seeing the atom as Democritus did.
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