Because the principle of purposiveness must be open-ended in its range of applicability, the possibility always remains open to judgment of construing all of nature in mechanistic terms, and indeed given the option, the intentional direction of our cognitive powers is such that they will always lead us to prefer such an interpretation, since we will prefer what brings all of nature within our ambit. If we follow this inclination, which is so deeply rooted in our nature that it grows together with and indeed gives life to our scientific activity, then we give free rein to our cognitive powers and simply let their own self-born orientation direct us in our relation to things. However reckless this might seem, if all the same this is the direction which comes to us through the unimpeded activity our most characteristic powers, would this not be most human?
But this ramification of the principle of purposiveness has a companion growing almost invisibly alongside it: namely, the critical power which retrospectively reflects on and clarifies the origin of science. And this power begins with a presupposition contrary to that which judgment wishes to arrogate to itself: that the cognitive powers are limited, and that these limitations present themselves to view purposively for the ordering of cognitive ambition, rather than for meeting its intention. This presupposition will be found in no one of the powers into which Kant divides cognition, as though he were doing so exhaustively—and this is perhaps the strangest feature of Kant's thought, that he omits to provide or even look for conditions of possibility for that mode of attention which facilitates his entire project. Whether this silence is a failure of self-consciousness or rather a supreme tact of the true charioteer seems to be the question, although perhaps it is no question at all—since it is at least suggestive of the highest human condition if not true to say that failure of self-consciousness is the essence of tact, just as Douglas Adams has imagined the secret of flight as consisting in being able to throw oneself at the ground, and miss.