The princely scholastic Pico de Mirandula already saw that reason is the faculty of abstract ideas, and understanding the faculty of ideas of perception. For in his book, “_De Imaginatione_,” ch. 11, he carefully distinguishes understanding and reason, and explains the latter as the discursive faculty peculiar to man, and the former as the intuitive faculty, allied to the kind of knowledge which is proper to the angels, and indeed to God. Spinoza also characterises reason quite correctly as the faculty of framing general conceptions (Eth., ii. prop. 40, schol. 2). Such facts would not need to be mentioned if it were not for the tricks that have been played in the last fifty years by the whole of the philosophasters of Germany with the conception _reason_. For they have tried, with shameless audacity, to smuggle in under this name an entirely spurious faculty of immediate, metaphysical, so-called super-sensuous knowledge. The reason proper, on the other hand, they call _understanding_, and the understanding proper, as something quite strange to them, they overlook altogether, and ascribe its intuitive functions to sensibility. In the case of all things in this world new drawbacks or disadvantages cleave to every source of aid, to every gain, to every advantage; and thus reason also, which gives to man such great advantages over the brutes, carries with it its special disadvantages, and opens for him paths of error into which the brutes can never stray. Through it a new species of motives, to which the brute is not accessible, obtains power over his will. These are the _abstract_ motives, the mere thoughts, which are by no means always drawn from his own experience, but often come to him only through the talk and example of others, through tradition and literature. Having become accessible to thought, he is at once exposed to error. But every error must sooner or later do harm, and the greater the error the greater the harm it will do. The individual error must be atoned for by him who cherishes it, and often he has to pay dearly for it. And the same thing holds good on a large scale of the common errors of whole nations. Therefore it cannot too often be repeated that every error wherever we meet it, is to be pursued and rooted out as an enemy of mankind, and that there can be no such thing as privileged or sanctioned error. The thinker ought to attack it, even if humanity should cry out with pain, like a sick man whose ulcer the physician touches. The brute can never stray far from the path of nature; for its motives lie only in the world of perception, where only the possible, indeed only the actual, finds room. On the other hand, all that is only imaginable, and therefore also the false, the impossible, the absurd, and senseless, enters into abstract conceptions, into thoughts and words. Since now all partake of reason, but few of judgment, the consequence is that man is exposed to delusion, for he is