Aletheia

Aletheia (Ancient Greek: ἀλήθεια) is truth or disclosure in philosophy. It was used in Ancient Greek philosophy and revived in the 20th century by Martin Heidegger.

It is a Greek word variously translated as "unclosedness", "unconcealedness", "disclosure" or "truth". The literal meaning of the word ἀ–λήθεια is "the state of not being hidden; the state of being evident." It also means factuality or reality. It is the opposite of lethe, which literally means "oblivion", "forgetfulness", or "concealment".

In the early to mid 20th-century, Martin Heidegger brought renewed attention to the concept of aletheia, by relating it to the notion of disclosure, or the way in which things appear as entities in the world. While he initially referred to aletheia as "truth", specifically a form that is pre-Socratic in origin, Heidegger eventually corrected this interpretation, writing:

To raise the question of aletheia, of disclosure as such, is not the same as raising the question of truth. For this reason, it was inadequate and misleading to call aletheia, in the sense of opening, truth."

Heidegger gave an etymological analysis of aletheia and drew out an understanding of the term as 'unconcealedness'. Thus, aletheia is distinct from conceptions of truth understood as statements which accurately describe a state of affairs (correspondence), or statements which fit properly into a system taken as a whole (coherence). Instead, Heidegger focused on the elucidation of how an ontological "world" is disclosed, or opened up, in which things are made intelligible for human beings in the first place, as part of a holistically structured background of meaning.

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