Democritus

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Democritus

Democritus
Full name Democritus
Born ca. 460 BC
Abdera, Thrace
Died ca. 370 BC (Aged 90)

Era Pre-Socratic philosophy
Region Western Philosophy
School Pre-Socratic philosophy
Main interests metaphysics / mathematics / astronomy
Notable ideas distant star theory

Democritus (Greek: Δημόκριτος, Dēmokritos, "chosen of the people") (ca. 460 BCE – ca. 370 BC) was an Ancient Greek philosopher born in Abdera, Thrace, Greece.[1] He was an influential pre-Socratic philosopher and pupil of Leucippus, who formulated an atomic theory for the cosmos.[2] Democritus was also known for being the first person for putting his ideas about atoms.

His exact contributions are difficult to disentangle from his mentor Leucippus, as they are often mentioned together in texts. Their speculation on atoms, taken from Leucippus, bears a passing and partial resemblance to the nineteenth-century understanding of atomic structure that has led some to regard Democritus as more of a scientist than other Greek philosophers; nevertheless their ideas rested on very different bases.[3] Largely ignored in Athens, Democritus was nevertheless well-known to his fellow northern-born philosopher Aristotle. Plato is said to have disliked him so much that he wished all his books burnt.[1] Many consider Democritus to be the "father of modern science".[4]

Life

Democritus was born in the city of Abdera in Thrace, an Ionian colony of Teos,[5] although some called him a Milesian.[6] His year of birth was 460 BC according to Apollodorus, who is probably more reliable than Thrasyllus who placed it ten years earlier.[7] John Burnet has argued that the date of 460 is "too early", since according to Diogenes Laërtius ix.41, Democritus said that he was a "young man (neos)" during Anaxagoras' old age (circa 440–428).[8] It was said that Democritus' father was so wealthy that he received Xerxes on his march through Abdera. Democritus spent the inheritance which his father left him on travels into distant countries, to satisfy his thirst for knowledge. He travelled to Asia, and was even said to have reached India and Ethiopia.[9] We know that he wrote on Babylon and Meroe; he must also have visited Egypt, and Diodorus Siculus states that he lived there for five years.[10] He himself declared[11] that among his contemporaries none had made greater journeys, seen more countries, and met more scholars than himself. He particularly mentions the Egyptian mathematicians, whose knowledge he praises. Theophrastus, too, spoke of him as a man who had seen many countries.[12] During his travels, according to Diogenes Laërtius, he became acquainted with the Chaldean magi. A certain "Ostanes", one of the magi accompanying Xerxes was also said to have taught him.[13]

After returning to his native land he occupied himself with natural philosophy. He traveled throughout Greece to acquire a knowledge of its culture. He mentions many Greek philosophers in his writings, and his wealth enabled him to purchase their writings. Leucippus, the founder of the atomism, was the greatest influence upon him. He also praises Anaxagoras.[14] Diogenes Laertius says that he was friends with Hippocrates.[15] He may have been acquainted with Socrates, but Plato does not mention him and Democritus himself is quoted as saying, "I came to Athens and no one knew me."[16]. Though Aristotle viewed him as a pre-Socratic[17], it should be noticed that since Socrates was born ca. 469 BC (about 9 years before Democritus), it is very possible that Aristotle's remark was not meant to be a chronological one, but directed towards his philosophical similarity with other pre-Socratic thinkers.

The many anecdotes about Democritus, especially in Diogenes Laërtius, attest to his disinterestedness, modesty, and simplicity, and show that he lived exclusively for his studies. One story has him deliberately blinding himself in order to be less disturbed in his pursuits;[18] it may well be true that he lost his sight in old age. He was cheerful, and was always ready to see the comical side of life, which later writers took to mean that he always laughed at the foolishness of people.[19]

He was highly esteemed by his fellow-citizens, "because," as Diogenes Laërtius says, "he had foretold them some things which events proved to be true," which may refer to his knowledge of natural phenomena. According to Diodorus Siculus,[20] Democritus died at the age of 90, which would put his death around 370 BC, but other writers have him living to 104,[21] or even 109.[22]

Popularly known as the Laughing Philosopher, the terms Abderitan laughter, which means scoffing, incessant laughter, and Abderite, which means a scoffer, are derived from Democritus.[23]

Philosophy and science

Democritus followed in the tradition of Leucippus, who seems to have come from Miletus, and he carried on the scientific rationalist philosophy associated with that city. They were both strict determinists and thorough materialists, believing everything to be the result of natural laws, and they will have nothing to do with chance or randomness. Unlike Aristotle or Plato, the atomists attempted to explain the world without the presuppositions of purpose, prime mover, or final cause. For the atomists questions should be answered with a mechanistic explanation ("What earlier circumstances caused this event?"), while their opponents searched for teleological explanations ("What purpose did this event serve?"). The history of modern science has shown that mechanistic questions lead to scientific knowledge, especially in physics, while the teleological question can be useful in biology, in adaptationist reasoning at providing proximate explanations, though the deeper evolutionary explanations are thoroughly mechanistic. The atomists looked for mechanistic questions, and gave mechanistic answers. Their successors until the Renaissance became occupied with the teleological question, which ultimately hindered progress.[24]

Atomic hypothesis

The theory of Democritus and Leucippus held that everything is composed of "atoms", which are physically, but not geometrically, indivisible; that between atoms lies empty space; that atoms are indestructible; have always been, and always will be, in motion; that there are an infinite number of atoms, and kinds of atoms, which differ in shape, and size. Of the mass of atoms, Democritus said "The more any indivisible exceeds, the heavier it is." But their exact position on weight of atoms is disputed.[1]

Leucippus is widely credited with being the first to develop the theory of atomism. Nevertheless, this notion has been called into question by some scholars. Newton, for instance, credits the obscure Moschus the Phoenician (whom he believed to be the biblical Moses) as the inventor of the idea.[25] The Stanford Encyclopedia of Philosophy notes, "This theologically motivated view does not seem to claim much historical evidence, however."[26]

Democritus, along with Leucippus and Epicurus, proposed the earliest views on the shapes and connectivity of atoms. They reasoned that the solidness of the material corresponded to the shape of the atoms involved. Thus, iron atoms are solid and strong with hooks that lock them into a solid; water atoms are smooth and slippery; salt atoms, because of their taste, are sharp and pointed; and air atoms are light and whirling, pervading all other materials.[27] Democritus was the main proponent of this view. Using analogies from our sense experiences, he gave a picture or an image of an atom that distinguished them from each other by their shape, their size, and the arrangement of their parts. Moreover, connections were explained by material links in which single atoms were supplied with attachments: some with hooks and eyes others with balls and sockets.[28] The Democritean atom is an inert solid (merely excluding other bodies from its volume) that interacts with other atoms mechanically. In contrast, modern, quantum-mechanical atoms interact via electric and magnetic force fields and are far from inert.

Aristotle criticized the atomists for not providing an account for the cause of the original motion of atoms. The theory of the atomists appears to be more nearly that of modern science than any other theory of antiquity. However, their theories had no real empirical basis, so their belief was devoid of any solid foundation. The atomists were seeking plausible explanations for the world, and can be viewed as having hit on a hypothesis for which, two thousand years later, some evidence happened to be found.[29]

Void hypothesis

The atomistic void hypothesis was a response to the paradoxes of Parmenides and Zeno, the founders of metaphysical logic, who put forth difficult to answer arguments in favor of the idea that there can be no movement. They held that any movement would require a void—which is nothing—but a nothing cannot exist. The Parmenidean position was "You say there is a void; therefore the void is not nothing; therefore there is not the void." The position of Parmenides appeared validated by the observation that where there seems to be nothing there is air, and indeed even where there is not matter there is something, for instance light waves.

The atomists agreed that motion required a void, but simply ignored the argument of Parmenides on the grounds that motion was an observable fact. Therefore, they asserted, there must be a void. This idea survived in a refined version as Newton's theory of absolute space, which met the logical requirements of attributing reality to not-being. Einstein's theory of relativity provided a new answer to Parmenides and Zeno, with the insight that space by itself is relative and cannot be separated from time as part of a generally curved space-time manifold. Consequently, Newton's refinement is now considered superfluous.[30]

Epistemology

The knowledge of truth according to Democritus is difficult, since the perception through the senses is subjective. As from the same senses derive different impressions for each individual, then through the sense-impressions we cannot judge the truth. We can only interpret the sense data through the intellect and grasp the truth, because the truth (aletheia) is at the bottom (en bythoe).

“And again, many of the other animals receive impressions contrary to ours; and even to the senses of each individual, things do not always seem the same. Which then, of these impressions are true and which are false is not obvious; for the one set is no more true than the other, but both are alike. And this is why Democritus, at any rate, says that either there is no truth or to us at least it is not evident.”[31] “Democritus says: By convention hot, by convention cold, but in reality atoms and void, and also in reality we know nothing, since the truth is at bottom.”[32]

There are two kinds of knowing, the one he calls “legitimate” (gnesie: genuine) and the other “bastard” (skotie: obscure). The “bastard” knowledge is concerned with the perception through the senses, therefore it is insufficient and subjective. The reason is that the sense-perception is due to the effluences of the atoms (aporroai) from the objects to the senses. When these different shapes of atoms come to us, they stimulate our senses according to their shape, and our sense-impressions arise from those stimulations.[33]