It is surprising that men, otherwise acute, can think it possible to distinguish between higher and lower desires, according as the ideas which are connected with the feeling of pleasure have their origin in the senses or in the understanding; for when we inquire what are the determining grounds of desire, and place them in some expected pleasantness, it is of no consequence whence the idea of this pleasing object is derived, but only how much it pleases. Whether an idea has its seat and source in the understanding or not, if it can only determine the choice by presupposing a feeling of pleasure in the subject, it follows that its capability of determining the choice depends altogether on the nature of the inner sense, namely, that this can be agreeably affected by it. However dissimilar ideas of objects may be, though they be ideas of the understanding, or even of the reason in contrast to ideas of sense, yet the feeling of pleasure, by means of which they constitute the determining principle of the will (the expected satisfaction which impels the activity to the production of the object), is of one and the same kind, not only inasmuch as it can only be known empirically, but also inasmuch as it affects one and the same vital force which manifests itself in the faculty of desire, and in this respect can only differ in degree from every other ground of determination. Otherwise, how could we compare in respect of magnitude two principles of determination, the ideas of which depend upon different faculties, so as to prefer that which affects the faculty of desire in the highest degree. The same man may return unread an instructive book which he cannot again obtain, in order not to miss a hunt; he may depart in the midst of a fine speech, in order not to be late for dinner; he may leave a rational conversation, such as he otherwise values highly, to take his place at the gaming-table; he may even repulse a poor man whom he at other times takes pleasure in benefiting, because he has only just enough money in his pocket to pay for his admission to the theatre. If the determination of his will rests on the feeling of the agreeableness or disagreeableness that he expects from any cause, it is all the same to him by what sort of ideas he will be affected. The only thing that concerns him, in order to decide his choice, is, how great, how long continued, how easily obtained, and how often repeated, this agreeableness is. Just as to the man who wants money to spend, it is all the same whether the gold was dug out of the mountain or washed out of the sand, provided it is everywhere accepted at the same value; so the man who cares only for the enjoyment of life does not ask whether the ideas are of the understanding or the senses, but only how much and how great pleasure they will give for the longest time. It is only those that would gladly deny to pure reason the power of determining the will, without the presupposition of any feeling, who could deviate so far from their own exposition as to describe as quite heterogeneous what they have themselves previously brought under one and the same principle. Thus, for example, it is observed that we can find pleasure in the mere exercise of power, in the consciousness of our strength of mind in overcoming obstacles which are opposed to our designs, in the culture of our mental talents, etc.; and we justly call these more refined pleasures and enjoyments, because they are more in our power than others; they do not wear out, but rather increase the capacity for further enjoyment of them, and while they delight they at the same time cultivate. But to say on this account that they determine the will in a different way and not through sense, whereas the possibility of the pleasure presupposes a feeling for it implanted in us, which is the first condition of this satisfaction; this is just as when ignorant persons that like to dabble in metaphysics imagine matter so subtle, so supersubtle that they almost make themselves giddy with it, and then think that in this way they have conceived it as a spiritual and yet extended being. If with Epicurus we make virtue determine the will only by means of the pleasure it promises, we cannot afterwards blame him for holding that this pleasure is of the same kind as those of the coarsest senses. For we have no reason whatever to charge him with holding that the ideas by which this feeling is excited in us belong merely to the bodily senses. As far as can be conjectured, he sought the source of many of them in the use of the higher cognitive faculty, but this did not prevent him, and could not prevent him, from holding on the principle above stated, that the pleasure itself which those intellectual ideas give us, and by which alone they can determine the will, is just of the same kind. Consistency is the highest obligation of a philosopher, and yet the most rarely found. The ancient Greek schools give us more examples of it than we find in our syncretistic age, in which a certain shallow and dishonest system of compromise of contradictory principles is devised, because it commends itself better to a public which is content to know something of everything and nothing thoroughly, so as to please every party.

The principle of private happiness, however much understanding and reason may be used in it, cannot contain any other determining principles for the will than those which belong to the lower desires; and either there are no [higher] desires at all, or pure reason must of itself alone be practical; that is, it must be able to determine the will by the mere form of the practical rule without supposing any feeling, and consequently without any idea of the pleasant or unpleasant, which is the matter of the desire, and which is always an empirical condition of the principles. Then only, when reason of itself determines the will (not as the servant of the inclination), it is really a higher desire to which that which is pathologically determined is subordinate, and is really, and even specifically, distinct from the latter, so that even the slightest admixture of the motives of the latter impairs its strength and superiority; just as in a mathematical demonstration the least empirical condition would degrade and destroy its force and value. Reason, with its practical law, determines the will immediately, not by means of an intervening feeling of pleasure or pain, not even of pleasure in the law itself, and it is only because it can, as pure reason, be practical, that it is possible for it to be legislative.