M. Comte's theory is still more vulnerable at another point. The fundamental assumption on which it is based is utterly groundless. It amounts to this, that all knowledge of causes, whether efficient or final, is interdicted to man, and incapable of being reached by any exertion of his faculties.[87] He tells us that Theology is impossible, for this reason, that, in the view of the Positive Philosophy, all knowledge of causes is absolutely excluded; nay, he admits that Theology is inevitable if we inquire into causes at all. We know of no simpler or more effectual method of dealing with his specious sophistry on this subject, than by showing that, if his general principle be conclusive against the knowledge of God, it is equally conclusive against the knowledge of any other being or cause; just as Sir James Mackintosh dealt with the skeptical philosophy of Hume, when, with admirable practical sagacity, he said: "As those dictates of experience which regulate conduct must be the objects of belief, all objections which attack them, in common with the principles of reasoning, must be utterly ineffectual. Whatever attacks every principle of belief, can destroy none. As long as the foundations of knowledge are allowed to remain on the same level with the maxims of life, the whole system of human conviction must continue undisturbed.... Skepticism has practical consequences of a very mischievous nature. This is because its _universality_ is not steadily kept in view and constantly borne in mind. If it were, the above short and plain remark would be an effectual antidote to the poison. But, in practice, it is an armory from which weapons are taken to be employed against _some_ opinions, while it is hidden from notice that the same weapons would equally cut down _every other_ conviction. It is thus that Mr. Hume's _theory of causation_ is used as an answer to arguments for the existence of the Deity, without warning the reader that it would equally lead him to expect--that _the sun will not rise to-morrow_."[88]