This unique diagram sums up many different views about the relation between knowledge, experience and reality (or between thought, experience and things (or between epistemology, phenomenology and ontology)).
  • the outer circle represents reality, all reality, whether we can access it or not

  • the triangle represents the three ways in which we can approach reality according to three perspectives:
  • o stands for ontos and it refers to reality as it is (what there is)
  • j stands for phenomenon and it referst to reality as it appears (what we have an experience of)
  • e stands for episteme and it refers to reality as it is knows (what we know)

  • the inner circle represents a simplified version of reality, a version that become popular after Galileo and Descartes and afterwards. It is the idea that reality can be split in a mental and a physical domain. Thus it is smaller than the triangle since it is a subset of it. And the inner circle is divided sharply in two halves (the black and the white) to express the (wrong) assumption that reality is divided in two unmixable halves

PS. I'm really sorry but a slightly wrong version of this diagram circulated (and it can still be found in my some of my works published before January 2008). In such a version, instead of the j letter, there is the p letter. I apologize for such a confusion due only to my poor knowledge of the Greek alphabet.