Category: Philosophical theories

Plato and the sciences of his time

Plato, during the fifty years he was active as an author, becomes all the more favourably inclined toward the science of his time, in the shaping of which an important contribution was made by himself and his circle.

The word “science”

The word “επιστήμων” is already recorded in Homer (Odyssey β 374) and signifies the “knowledgeable”, “prudent” person, just as it does later in Sophocles, Thucydides and the orators. In Plato the older notion is retained, yet the newer, more specific sense of it is also detected (as the person possessing valid knowledge). “Eπιστήμη” at first means good knowledge in the sense of experience, of skill, then takes on the meaning of knowledge in general (Sophocles, Antigone 721), only to come to mean in Plato and Aristotle the stricter sense of valid specific knowledge, set in contrast to τέχνη on one hand and to δόξα on the other. The adjective “επιστημονικός” is first attested in Aristotle.

The word “science”, therefore, acquires its specific sense only in the beginning of the fourth century BCE in a development starting with Plato and reaching its completion with Aristotle. This means that it is at this time that the need is felt for a field of specific knowledge to be marked out from the sum of given knowledge, arts and skills.

The sciences during the fourth century

1. Astronomy. The fifth century adds the knowledge imported from the East to the physiological knowledge that every people possesses for everyday needs and that is the result of observing the sky and the meteorological phenomena: the seven planets, the phases of the moon, the zodiac circle. The inclination of elliptical orbits and the inequality of the seasons are considered to be Greek discoveries of the same period. The attempt to establish an effective calendar begins in Athens during the second half of the fifth century with Meton and Euctemon and is continued during the fourth century. The first adequate astronomical theory of planetary movements, a theory respecting the astronomical phenomena and possessing internal consistency, is developed by Eudoxus in Plato’s time.

2. Theory of music (“harmony”). The theoretical study of music develops in Pythagorean circles. In Socrates’ time harmony has already acquired unified and sophisticated theory with Archytas and Philolaus.

3. Medicine. Systematic medical knowledge is already attested at the beginning of the fifth century with Alcmaeon and Empedocles. Scholars agree that at least some of Hippocrates’ treatises, which testify to an empirical viewpoint and a rationalist mentality, are Preplatonic. Yet medicine was never included in the sciences in antiquity -- it remained a respectable and useful “art”.

4. Natural sciences. Biological knowledge is already mentioned in Anaximander. In the study of living organisms important progress is made with Empedocles and the Atomists, to the extent that one may even speak of the beginnings of chemistry. One can detect physics, in the sense of the theory of movement, only at the level of a methodological approach with Anaxagoras and mostly with Democritus. This knowledge is treated systematically and expanded upon in Plato’s Timaeus, as well as in Aristotle’s works on physics and biology.

Plato and the sciences

Plato’s activity as an author spans the first fifty years of the fourth century BCE. During this long period his stance toward the sciences changes. In the early dialogues the Platonic Socrates is portrayed as indifferent to, or even suspicious of, the naturalistic and mathematical tradition of his contemporaries and predecessors. His own interest is limited to ethical issues, while scientific aptitude is often a boasting point of his Sophist rivals. During the middle period, the Meno, the Phaedo and the Republic being significant milestones, one notices an impressive elevation of the import of mathematics. Mathematical knowledge is regarded as a model of precision and validity.

In the later dialogues Plato’s scientific interests are significantly expanded not only in the direction of the social arts (rhetoric, legislation, medicine), but also toward the entire spectrum of the natural sciences. In the Timaeus Plato develops a complete teleological world-picture, which serves simultaneously as an encyclopaedia of fourth-century natural sciences. In the so-called “unwritten doctrines” he also attempts to incorporate basic mathematical concepts (unit, infinity) in the heart of his metaphysics.

Plato’s familiarity with the sciences, and especially with mathematics, does not imply an uncritical acceptance of current practices. Whenever Plato deals with scientific knowledge, he does not fail to stress that one should not conflate scientific knowledge with usefulness. What he appreciates in the sciences is their relation to truth.

“My question, dear Protarchus, was not as yet what art or science surpasses all others by being the greatest and best and most useful to us: what I am trying to find out at present is which art, however little and of little use, has the greatest regard for clearness, exactness, and truth.” [Philebus 58b-c]

But even pure science, free from any ties to usefulness, can never reach absolute cognitive validity. This role is assigned to philosophy, which is knowledge of the immutable and eternal Forms. By definition the cognitive range of the sciences is limited, since they retain their connection to the sensible world and its unstable and changing entities. In the Timaeus natural theory will be named “εικώς λόγος [likely account]”, i.e. plausible narrative. It is a likely and acceptable account of reality, showing us that the universe is regular, mathematically organised and rational, yet such an account claims no part of truth.

“And can we say that any of these things becomes certain, if tested by the touchstone of strictest truth, since none of them ever was, will be, or is in the same state? [...] That fixed and pure and true and what we call unalloyed knowledge has to do with the things which are eternally the same without change or mixture, or with that which is most akin to them” [Philebus 59a-c]

However, one should not think that, while Plato’s philosophy develops, the sciences of the fourth century have ceased to develop. In fact one detects parallel developments in philosophy and the sciences, parallel developments that are often indicative of reciprocal influences. Plato, hence, changes his stance toward a dynamic and developing cognitive field, in whose shaping he has important contributions himself.

Author: Vassilis Kalfas
  • Dicks, D.R. Early Greek Astronomy to Aristotle. Λονδίνο, 1970.
  • Neugebauer, O. A History of Ancient Mathematical Astronomy. Nέα Yόρκη / Xαϊλδεβέργη / Bερολίνο, 1975.
  • Vlastos, G. Socrates. Ironist and Moral Philosopher. Cambridge, 1991.
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