Dionysius of Chalcedon was a Greek philosopher

Greek philosophy

Ancient Greek philosophy arose in the 6th century BCE and continued through the Hellenistic period, at which point Ancient Greece was incorporated in the Roman Empire...

 and dialectician

Dialectician

A dialectician is a philosopher who views the world in terms of complementary opposites and the interactions thereof. In popular usage, the central feature of dialectic is the concept of "thesis, antithesis, synthesis" - when an idea or phenomenon arises, it carries within itself the seed of its...

 connected with the Megarian school. He was a native of Chalcedon

Chalcedon

Chalcedon , sometimes transliterated as Chalkedon) was an ancient maritime town of Bithynia, in Asia Minor, almost directly opposite Byzantium, south of Scutari . It is now a district of the city of Istanbul named Kadıköy...

 on the coast of Bithynia

Bithynia

Bithynia was an ancient region, kingdom and Roman province in the northwest of Asia Minor, adjoining the Propontis, the Thracian Bosporus and the Euxine .-Description:...

. Dionysius was the person who first used the name Dialecticians to describe a splinter group within the Megarian school "because they put their arguments into the form of question and answer." One area of activity for the dialecticians was the framing of definition

Definition

A definition is a passage that explains the meaning of a term , or a type of thing. The term to be defined is the definiendum. A term may have many different senses or meanings...

s, and Aristotle

Aristotle

Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...

 criticises a definition of life by Dionysius in his Topics

Topics (Aristotle)

The Topics is the name given to one of Aristotle's six works on logic collectively known as the Organon. The other five are:*Categories*De Interpretatione*Prior Analytics*Posterior Analytics*On Sophistical Refutations...

:

This is, moreover, what happens to Dionysius' definition of "life" when stated as "a movement of a creature sustained by nutriment, congenitally present with it"

Dionysius is also reported to have taught Theodorus the Atheist

Theodorus the Atheist

Theodorus the Atheist, of Cyrene, was a philosopher of the Cyrenaic school. He lived in both Greece and Alexandria, before ending his days in his native city of Cyrene. As a Cyrenaic philosopher, he taught that the goal of life was to obtain joy and avoid grief, and that the former resulted from...

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