In the propositions in which Descartes gives in his own way the ground of this great and most important principle, there is found a naïve and empirical system of reasoning. This is an example: “Because we were born as children, and formed all manner of judgments respecting sensuous things before we had the perfect use of our reason, we are through many preconceived ideas hindered from the knowledge of the truth. From these we appear not to be able to free ourselves in any other way but by once in our lives striving to doubt that respecting which we have the very slightest suspicion of an uncertainty. Indeed it is really desirable to hold as false everything in respect to which we have any doubt, so that we may find more clearly what is most certain and most knowable. Yet this doubt has to be limited to the contemplation of the truth, for in the conduct of our life we are compelled to choose the probable, since there the opportunity for action would often pass away before we could solve our doubts. But here, where we have only to deal with the search for truth, we may very reasonably doubt whether any thing sensuous and perceptible exists—in the first place because we find that the senses often deceive us and it is prudent not to trust in what has even once deceived us, and then because every day in dreaming we think we feel or see before ourselves innumerable things which never were, and to the doubter no signs are given by which he can safely distinguish sleeping from waking. We shall hereby likewise doubt everything else, even mathematical propositions, partly because we have seen that some err even in what we hold most certain, and ascribe value to what to us seems false, and partly because we have heard that a God exists who has created us, and who can do everything, so that He may have created us liable to err. But if we conceive ourselves not to derive our existence from God, but from some other source, perhaps from ourselves, we are all the more liable, in that we are thus imperfect, to err. But we have so far the experience of freedom within us that we can always refrain from what is not perfectly certain and well founded.”[156] The demand which rests at the basis of Descartes’ reasonings thus is that what is recognized as true should be able to maintain the position of having the thought therein at home with itself. The so-called immediate intuition and inward revelation, which in modern times is so highly regarded, has its place here. But because in the Cartesian form the principle of freedom as such is not brought into view, the grounds which are here advanced are for the most part popular.