As we have already mentioned, philosophy, for Deleuze, is inseparable from ‘critique’. He admires Kant for having brought a revolution to philosophy by means of his transcendental critique. The domain of the transcendental is not the domain of the transcendent. Kant undermines the traditional philosophical distinctions, in particular with his notion of ‘phenomenon’, which has a completely different meaning from the meaning that this term had acquired in the philosophical tradition. Since Plato, philosophers had distinguished the appearance of a thing from its metaphysical essence. They had opposed the ‘apparent world’ of sensuous, perishable and illusive appearances to the transcendent, ‘intelligible world’ of eternal and true essences. Kant replaces the disjunctive couple appearance/essence with the conjunctive couple of that which appears (Erscheinung) and its transcendental conditions of apparition. The Kantian phenomenon is no longer a deceptive simulacrum or an inferior copy related to an original essence, but an object of experience related to transcendental conditions which constitute it as a possible object for us, that is as having a sense or signification. This means that the dimension of signification takes the place of the metaphysical essence. Truth is no longer hidden in a metaphysical realm, unattainable in principle, but can be attained in experience on the premise that experiential cognition complies with the transcendental conditions of experience. Transcendental logic provides a necessary criterion for truth, namely the relation to an object (which is the dimension of signification).