The only decided, direct restriction and disturbance which the will can suffer from the intellect as such may indeed be the quite exceptional one, which is the consequence of an abnormally preponderating development of the intellect, thus of that high endowment which has been defined as genius. This is decidedly a hindrance to the energy of the character, and consequently to the power of action. Hence it is not the really great minds that make historical characters, because they are capable of bridling and ruling the mass of men and carrying out the affairs of the world; but for this persons of much less capacity of mind are qualified when they have great firmness, decision, and persistency of will, such as is quite inconsistent with very high intelligence. Accordingly, where this very high intelligence exists we actually have a case in which the intellect directly restricts the will.
6. In opposition to the hindrances and restrictions which it has been shown the intellect suffers from the will, I wish now to show, in a few examples, how, conversely, the functions of the intellect are sometimes aided and heightened by the incitement and spur of the will; so that in this also we may recognise the primary nature of the one and the secondary nature of the other, and it may become clear that the intellect stands to the will in the relation of a tool.
A motive which affects us strongly, such as a yearning desire or a pressing need, sometimes raises the intellect to a degree of which we had not previously believed it capable. Difficult circumstances, which impose upon us the necessity of certain achievements, develop entirely new talents in us, the germs of which were hidden from us, and for which we did not credit ourselves with any capacity. The understanding of the stupidest man becomes keen when objects are in question that closely concern his wishes; he now observes, weighs, and distinguishes with the greatest delicacy even the smallest circumstances that have reference to his wishes or fears. This has much to do with the cunning of half-witted persons, which is often remarked with surprise. On this account Isaiah rightly says, _vexatio dat intellectum_, which is therefore also used as a proverb. Akin to it is the German proverb, “_Die Noth ist die Mutter der Künste_” (“Necessity is the mother of the arts”); when, however, the fine arts are to be excepted, because the heart of every one of their works, that is, the conception, must proceed from a perfectly will-less, and only thereby purely objective, perception, if they are to be genuine. Even the understanding of the brutes is increased considerably by necessity, so that in cases of difficulty they accomplish things at which we are astonished. For example, they almost all calculate that it is safer not to run away when they believe they are not seen; therefore the hare lies still in the furrow of the field and lets the sportsman pass close to it; insects, when they cannot escape, pretend to be dead, &c. We may obtain a fuller knowledge of this influence from the special history of the self-education of the wolf, under the spur of the great difficulty of its position in civilised Europe; it is to be found in the second letter of Leroy’s excellent book, “_Lettres sur l’intelligence et la perfectibilité des animaux_.” Immediately afterwards, in the third letter, there follows the high school of the fox, which in an equally difficult position has far less physical strength. In its case, however, this is made up for by great understanding; yet only through the constant struggle with want on the one hand and danger on the other, thus under the spur of the will, does it attain that high degree of cunning which distinguishes it especially in old age. In all these enhancements of the intellect the will plays the part of a rider who with the spur urges the horse beyond the natural measure of its strength.