The Cartesian proofs have been much and keenly discussed. The one which founds on the fact of our existence and its limitations is manifestly _a posteriori_. The other two both proceed from the idea of a perfect being. The first is, that the idea of an all-perfect and unlimited being is involved in the very consciousness of imperfection and limitation. The imperfect can only be seen in the light of the perfect; the finite cannot be conceived of except in relation to the infinite. But can a finite and imperfect cause--like the human mind or the outward world--be reasonably supposed to originate the idea of an infinite and perfect being? Descartes holds that it cannot; that the idea of an infinite and perfect being can only be explained by the existence and operation of such a being. Was he correct in this judgment? Perhaps not; but what has been urged in refutation of it is probably by no means conclusive. It has been said that the ideas of infinity and perfection are mere generalisations from experience. But this is a statement which can only be proved on the principles of sensationalism, and never has been proved. It has been likewise said that these ideas are purely subjective, or, in other words, that there may be nothing whatever to correspond to them. But this is a meaningless collocation of words. No finite mind can conceive the infinite, for example, as within itself at all. The human mind can only think of the infinite as without itself. If the infinite be not objective, the idea of the infinite is false and delusive. The infinite, it has been further objected, means merely what is not finite; and the perfect what is not imperfect. So be it; the argument is as valid if the words be taken in that sense as in any other. Only do not add, as some do, that the perfect and the imperfect, the finite and the infinite, are mere verbal correlatives. Such a proposition can be spoken, but it cannot be thought; and it is most undesirable to divorce thought from speech. It has also been urged that all men have not the idea of perfection; that different men have different ideas thereof; and that in each man who possesses it the idea is constantly changing. This must be granted; but it does not affect the argument, which is founded on the existence of the idea of a perfect being, and not on the perfection of the idea itself.