Kehre

Martin Heidegger, the 20th-century German philosopher, produced a large body of work that intended a profound change of direction for philosophy. Such was the depth of change that he found it necessary to introduce a large number of neologisms, often connected to idiomatic words and phrases in the German language.

Two of his most basic neologisms, present-at-hand and ready-to-hand, are used to describe various attitudes toward things in the world. For Heidegger, such "attitudes" are prior to, i.e. more basic than, the various sciences of the individual items in the world. Science itself is an attitude, one that attempts a kind of neutral investigation. Other related terms are also explained below.

Heidegger's overall analysis is quite involved, taking in a lot of the history of philosophy. See Being and Time for a description of his overall project, and to give some context to these technical terms.

Heidegger's idea of aletheia, or disclosure (Erschlossenheit), was an attempt to make sense of how things in the world appear to human beings as part of an opening in intelligibility, as "unclosedness" or "unconcealedness". (This is Heidegger's usual reading of aletheia as Unverborgenheit, "unconcealment.") It is closely related to the notion of world disclosure, the way in which things get their sense as part of a holistically structured, pre-interpreted background of meaning. Initially, Heidegger wanted aletheia to stand for a re-interpreted definition of truth. However, he later corrected the association of aletheia with truth (see main article on aletheia for more information).

An assertion (as opposed to a question, a doubt or a more expressive sense) is apophantic. It is a statement that covers up meaning and just gives us something as present-at-hand. For Instance, "The President is on vacation", and, "Salt is Sodium Chloride" are sentences that, because of their apophantic character, can easily be picked-up and repeated in news and gossip by 'The They.' However, the real ready-to-hand meaning and context may be lost.

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