Son of the physician to the king
of Macedonia, in 367 B.C. he entered Plato's Academy in Athens, where
he stayed until his master's death in 347. After performing the role
of tutor to the future Macedonian king Alexander the Great, he settled
in Athens, where he founded, in 335, a famous school called the "Lyceum"
or "Peripatetic school". He was the author of fundamental works in
various camps of knowledge: The Organon (logical writings),
Metaphysica, Physica, On the Soul, The Nicomachean
Ethics, Economics, Politics, Poetics, Rhetoric.
Indeed, aristotelian thought has an
encyclopaedic character to it, investigating nearly every domain of
knowledge, organically and coherently, proceeding from a few fundamental
philosophical principles, such as the four causes, the dialectic between
potentiality and act, and the distinction between matter and form.
Aristotle's "physics" exploits a qualitative
analysis of natural phenomena, usually without recourse to mathematical
methods. In the aristotelian cosmology, the Earth - place of corruption
- was positioned at the centre of the Universe and composed of the
four elements: earth, water, air and fire, which moved naturally in
straight lines, either upwards, or downwards. The motions of the celestial
bodies (the Sun, the planets and the stars), on the other hand, were
uniform and circular. To explain the independent motion of the planets,
Aristotle imagined that they rotated on concentric spheres. Aristotle's
physics was cleansed in the thirteenth and fourteenth centuries, above
all by Saint Thomas Aquinas, of those ideas which were incompatible
with the Christian faith (such as the eternity of the world, the materiality
of the soul, etc.). It became the basis of university courses, remaining
more or less unchallenged until it came up against the claims of the
new mathematical and experimental science.
Among aristotelian theories of physics,
an important role is played by the doctrine which denies any reality
whatsoever to the void. According to Aristotle, an empty space is
nothing but a contradiction in terms, space (or rather "place", topos
in Greek), being nothing other than the limit of bodies, so that there
cannot be a space (place) without the presence of bodies. In the Fourth
Book of the Physics, in particular, Aristotle goes on to show
the paradoxes which, on the basis of this definition, would proceed
from the acceptance of the real existence of a void.