And they proceed to seek to establish the substantiality of the soul, hypostatizing the states of consciousness, and they begin by saying that this substance must be simple--that is, by opposing thought to extension, after the manner of the Cartesian dualism. And as Balmes was one of the spiritualist writers who have given the clearest and most concise form to the argument, I will present it as he expounds it in the second chapter of his _Curso de Filosofia Elemental_. "The human soul is simple," he says, and adds: "Simplicity consists in the absence of parts, and the soul has none. Let us suppose that it has three parts--A, B, C. I ask, Where, then, does thought reside? If in A only, then B and C are superfluous; and consequently the simple subject A will be the soul. If thought resides in A, B, and C, it follows that thought is divided into parts, which is absurd. What sort of a thing is a perception, a comparison, a judgement, a ratiocination, distributed among three subjects?" A more obvious begging of the question cannot be conceived. Balmes begins by taking it for granted that the whole, as a whole, is incapable of making a judgement. He continues: "The unity of consciousness is opposed to the division of the soul. When we think, there is a subject which knows everything that it thinks, and this is impossible if parts be attributed to it. Of the thought that is in A, B and C will know nothing, and so in the other cases respectively. There will not, therefore, be _one_ consciousness of the whole thought: each part will have its special consciousness, and there will be within us as many thinking beings as there are parts." The begging of the question continues; it is assumed without any proof that a whole, as a whole, cannot perceive as a unit. Balmes then proceeds to ask if these parts A, B, and C are simple or compound, and repeats his argument until he arrives at the conclusion that the thinking subject must be a part which is not a whole--that is, simple. The argument is based, as will be seen, upon the unity of apperception and of judgement. Subsequently he endeavours to refute the hypothesis of a communication of the parts among themselves. Balmes--and with him the _a priori_ spiritualists who seek to rationalize faith in the immortality of the soul--ignore the only rational explanation, which is that apperception and judgement are a resultant, that perceptions or ideas themselves are components which agree. They begin by supposing something external to and distinct from the states of consciousness, something that is not the living body which supports these states, something that is not I but is within me.