The symbol of the circle has been used throughout the history of philosophy as a universal metaphor for the notions of totality, wholeness, original perfection, the infinite, eternity, God, etc. In the following, I present some of the circle metaphors applied by philosophers, writers and artists.

Mythology

The ouroboros or uroboros (snake eating its own tail) is an ancient symbol for the eternal cycle of life, death and rebirth.

C. J....

This metaphysical question is one of the most fundamental questions in philosophy. It points to the ultimate reality or source that produces the plurality of physical and mental phenomena. The word 'existence' is applied to any singular entity that subsists in the time-space continuum of the universe. Existence is basically presence, being present to our experience, which furthermore means being an object of our mind, of our thinking. Things do not exist independently of our mind, but that does not mean that they are only objects or ideas of our mind. However, they become existent things (existants) for us through ...