Chrysippus is one of the most obscure philosophers that appears regularly in textbooks on the subject. How can this be, you ask? When, in 47 BC, the legions of Julius Caesar burnt the library at Alexandria, they destroyed the main body of his work. With this taking place approximately 160 years after his death, he has had little opportunity to explain himself to history. Evidence of his thinking still exists, but in the works of his contemporaries, and therefore we lack a comprehensive picture of his philosophy. What then do we know about him?

  • He was born circa 280 BC, and died circa 208 BC.
  • He was widely admired for his skill at logic.
  • He appears to have been the first thinker to establish truth-conditions for conditional statements. Put simply, he used the formulation "If... Then...", for example: "If I drop this glass to the ground, then it will shatter".
  • He was the third most prominent figure in the Stoic school of thinking, after Zeno and Cleanthes.
  • He believed in a recurring universe. The entirety of existence begins, plays out and then ends, and repeats doing so indefinitely He therefore predated some very interesting science by a couple of thousand years.
  • As a good stoic, he promoted the value of wisdom, rationality and virtue as the ingredients of a happy life.

He was, it would seem, a very clever man. It is a shame that due to some careless Roman arson, I am unable to conclude by quoting him.