54. Kant pretends that the argument in favor of the substantiality of the soul is not conclusive, because the pure categories, and consequently that of substance also, have absolutely no objective value, except in so far as applied to the diversity of an intuition subject to them: that is to say, the conception of substance is a purely logical function, without any objective value or meaning except as referred to sensible things, and as soon as we leave the sphere of sensibility, it can lead to no result. It is evident that the substantiality of the soul cannot be the object of sensible intuition; consequently, to apply to the soul the idea of substance is to extend the conception beyond what its nature allows. It must be confessed that Kant's reasoning is conclusive, if we admit his principles; and here we have a proof of the necessity of combating certain theories, which, because they are in the realm of abstractions, seem innocent, but in reality are most dangerous, on account of the results to which they lead. Such is the system of Kant as denying the objective value of the pure categories, and this is why I have combated it,[44] demonstrating: I. That indeterminate conceptions, and the general principles founded on them, have an objective value beyond the field of sensible experience, in respect to beings which are in nowise subject to our intuition; II. That it is not true that we have only sensible intuition, for we have intuitive knowledge of a pure intellectual order, above the sphere of sensibility. This doctrine overthrows the whole of Kant's argument, for it destroys its foundation. [44] See Bk. IV., Chs. XIII., XIV., XV., XVI., XXI., XXII.