Know thyself

Know thyself

These were the words inscribed almost as a warning in the pronaos of the Temple of Apollo in Delphi. It was Plato who actually transmitted this phrase via his dialogues. Indeed, he suggested the importance of looking inwards before making any decisions or taking any steps forward.

From https://exploringyourmind.com/the-origin-of-the-famous-saying-know-thyself/#google_vignette