Fichte confesses that in order to arrive at the primitive act, and separate from it all that does not really belong to it, we must suppose the rules of all reflection to be valid, and start with some one of the many universally admitted propositions. "Conceding us," he says, "this proposition, you must, at the same time, concede as act that which we desire to place as the principle of the whole _Doctrine of Science_; and the result of the reflection must be that this act is conceded to us as the principle together with the proposition. We take any fact of empirical consciousness, and strip it one after another of all its empirical determinations, until reduced to all its purity it contains that only which thought cannot absolutely exclude, and from which nothing further can be taken."[5] [5] _Ibid._ These words show that the German philosopher proposed ascending to a perfectly pure and wholly indeterminate act of consciousness, which, however, is impossible. Either he takes the act in a very broad sense, and understands by it the _substratum_ of all consciousness, in which case he only expresses in other words the idea of substance; or else he speaks of an act properly so called, that is, of some exercise of that activity, that spontaneity which we feel within ourselves; and in this sense the act of consciousness cannot be separated from all determination without destroying its individuality and existence. Man cannot think without thinking something, desire without desiring something, feel without feeling something, or reflect upon internal acts without fixing his reflection upon something. There is some determination in every act of consciousness: an act perfectly pure, abstracted from every thing, and wholly indeterminate, is impossible, absolutely impossible; subjectively, because the act of consciousness, although considered in the subject, requires some determination; objectively, because such an act is inconceivable as individual, and consequently as existing, since it offers nothing determinate to the mind. 81. Fichte's indeterminate act is only the idea of act in general. He imagined he had made a great discovery when he conceived nothing in the groundwork but the principle of act, that is, the idea of substance applied to that active being whose existence consciousness itself makes known to us. If we may be allowed to say candidly what we think, our opinion is, that Fichte, with all his analytical investigations, has not advanced philosophy one step towards the discovery of the first principle. We see from what has already been said how easy it is to stop him by simply demanding an account of the suppositions made on the first page of his book. Still, wishing, as we do, to oppose him with all fairness, we will not take up his ideas without allowing him to explain them himself.