“Philosophers are in the habit of indicating the object of judgement by the letter p. There is an insouciance with respect to this fateful letter. It stands ready quietly, unobstrusively, to assure us that we know what we are talking about. For example, when we do epistemology, we are interested in what it is for someone to know - know what? oh yes: p. If we inquire into rational requirements on action or intention, we ask what it is to be obliged to - what? oh yes: see to it that p, intend that, if p, then q, and so on. However, if we udnertake to reflect on thought, on its self-consciousness and its objectivity, then the letter p signifies the deepest question and the deepest comprehension. If only we understood the letter p, the whole world would be open to us.”