Democritus was a pre-Socratic philosopher, Greek mathematician, and disciple of Leucippus. He was born in Abdera, Thrace in the year 460 b.C. His birthplace was the capital of a Greek polis now located on the northern coast of Greece, near the island of Thasos. He studied with Chaldean scholar magicians, whom King Xerxes I of Persia accommodated at his father’s house, while he was part of a military campaign in the medical wards. Thanks to this, he managed to acquire knowledge of astrology and theology in his youth. He is considered a pre-Socratic philosopher for his thematic physics.
His career and works were developed between 460 and 370 before Christ. In his time as a researcher and theorist of theories, it is said that he made trips throughout Egypt where he stayed for 5 years learning geometry. He also traveled through Mesopotamia, Babylon, Ethiopia, and Persia in search of new knowledge. Also, it is said that he had the ability to predict the future and among his most recognized works was “Great Diacosmos” which represented him winning the 500 talents prize. His idea of writing the great diacosmos arose from the need to defend himself before those who accused him of squandering the inheritance that his father left him.
Democritus developed and complemented the atomic theory of the universe, which was initially proposed by his teacher Leucippus. That theory posited that the universe is constituted by large quantities of substantially identical, indivisible and indestructible atoms, these are constantly moving in a vacuum and the elements that make up the universe. There are differences between them only in their position, shape, and dimensions. Democritus posed some postulates to better explain his atomic theory, these were explained by logical reasoning, since the Greek philosophical theories did not support postulates by experiments.
The 3 postulates of the theory of Democritus are:
- The atoms are indivisible, eternal, incomprehensible, homogeneous and indivisible.
- Atoms differ in shape and size, but their internal qualities are equal.
- The properties of matter change according to the grouping of atoms.
Democritus also said that everything that surrounds nature is a mixture of atoms and vacuum, so he explained that atoms move naturally and consubstantially, and by the movement they make, they collide with each other and combine when their properties, characteristics, and forms allow it. The philosopher also explained that in the universe there are collisions between atoms that generate a kind of vortexes which give rise to various worlds that have a formation process and others that disappear quickly.
In the branch of geometry, Democritus demonstrated the following theorems:
- The volume of a cone is equal to one-third of the volume of a cylinder of equal base and height.
- The volume of a pyramid is one-third of the prism volume of equal base and height.
At the level of philosophy and ethics, Democritus was known for being the possible creator of the atomistic school and for relying on internal equilibrium, which for him was achieved through the control of the passions, through knowledge and prudence. Democritus also raised a thought related to happiness, which said that the natural aspiration of every individual is not so much the pleasure, but more the tranquility of spirit (euthymia); pleasure must be chosen, and pain avoided, but in the proper exclusion of pleasures is true happiness.