There is always another possibility. Such is, in the simplest terms, how I would summarise Jacques Derrida's ultimate teaching. This phrase, ‘there is always another possibility’, is one that we are able to conjugate in every tense. In a certain sense, it is time itself – a sort of transcendental schematism that secretly governs the categories of deconstruction.

There is always another possibility. In the present tense, this means: There is always something other than what is. In the future tense, this means: Another order of things may come to pass, even if one is unable to ‘see it coming’. This other possibility is the absolute arrivant, which Derrida has also called ‘the promise’. A promise can be a promise of good fortune or happiness; it can also be the possibility of the worst, or what Derrida, after Kant, calls radical evil.

There is always another possibility. In the past tense, this means: Our entire history, everything that ever was or has been, could have happened differently. A totally other possibility could have oriented history, which would have brought about another order of things. Other events could have taken place, which would have constituted another tradition. This concept of ‘the other possibility’ is not equivalent to the traditional concept of ‘the possible’, which, in the history of philosophy, is coupled with those of necessity and actuality. The other possibility, the totally other possibility, would be that to which no other category could possibly correspond – neither the necessary, nor the actual, not even the impossible.

Derrida tells us that we can do nothing but believe in this other possibility. What are the modalities of such a belief? This is the question to which I would like to respond here. In particular, I would like to examine the motifs of possibility and belief, of faith and the promise, such as they are embedded in Derrida's late texts. Even if it is clearly illegitimate to distinguish between different ‘periods’ in his oeuvre, it is nevertheless imperative to recognise the different emphases that exist within it.