On the Derived Forms of the Supreme Principle of the Kantian Ethics
It is well known that Kant laid down the supreme principle of his ethics in yet a second and quite different form in which it is expressed not merely indirectly as in the first, as an instruction on how it is to be sought, but directly. Starting at page 63, R. 55, he prepares the way for this, and indeed by very strange, stilted, and even distorted definitions of the concepts end and means, which, however, may be much more simply and correctly defined thus: End is the direct motive of an act of will, means the indirect motive (simplex sigillum veri). Kant, however, slips through his strange definitions to the proposition: “Man, and in general every rational being, exists as an end in himself.” But I must say frankly that “to exist as an end in oneself” is an unthinkable expression, a contradictio in adjecto. To be an end or aim means to be willed. Every aim or end in view exists only in reference to a will, and is the end of the will, that is (as I have said), the direct motive of it. Only in this relation has the concept end any meaning, which it loses as soon as it is torn away. But this essential relation necessarily excludes all in itself. “End in itself” is exactly like saying “friend in himself, enemy in himself, uncle in himself, north or east in itself, above or below in itself,” and so on. Basically, however, the case is the same with “end in itself” as with the “absolute ought.” Secretly, and even unconsciously underlying both, as their condition, is the same idea, namely, the theological. Nor does the absolute worth that is said to attach to such an alleged but inconceivable end in itself fare any better, for this too I must without mercy stamp as a contradictio in adjecto. Every worth is a quantity of comparison and even stands necessarily in a double relation. First, it is relative, in that it exists for someone; and secondly, it is comparative, in that it exists in comparison with something else by which it is valued or assessed. Outside these two relations, the concept worth loses all meaning; this is so clear that there is no need for further discussion. Now just as those two definitions offend against logic, so is genuine morality outraged by the proposition (page 65, R. 56) that beings devoid of reason (hence animals) are things and therefore should be treated merely as means that are not at the same time an end. In agreement with this, it is expressly stated in the Metaphysical Principles of the Doctrine of Virtue, §16, that “man can have no duty to any beings except human”; and then it says in §17 that “cruelty to animals is contrary to man’s duty to himself, because it deadens in him the feeling of sympathy for their sufferings, and thus a natural tendency that is very useful to morality in relation to other human beings is weakened.” Thus only for practice are we to have sympathy for animals, and they are, so to speak, the pathological phantom for the purpose of practicing sympathy for human beings. In common with the whole of Asia not tainted with Islam (that is, Judaism), I regard such propositions as revolting and abominable.
Confirmations of the Expounded Basis of Morals
Boundless compassion for all living beings is the firmest and surest guarantee of pure moral conduct, and needs no casuistry. Whoever is inspired with it will assuredly injure no one, will wrong no one, will encroach on no one’s rights; on the contrary, he will be lenient and patient with everyone, will forgive everyone, will help everyone as much as he cares, and all his actions will bear the stamp of justice, philanthropy, and Wing-kindness. On the other hand, if we attempt to say, “This man is virtuous but knows no compassion,” or, “He is an unjust and malicious man yet he is very compassionate,” the contradiction is obvious. Tastes differ, but I know of no finer prayer than the one which ends old Indian dramas (just as in former times English plays ended with a prayer for the King). It runs: “May all living beings remain free from pain.” . . .
The moral incentive advanced by me as the genuine, is further confirmed by the fact that the animals are also taken under its protection. In other European systems of morality they are badly provided for, which is most inexcusable. They are said to have no rights, and there is the erroneous idea that our behavior to them is without moral significance, or, as it is said in the language of that morality, there are no duties to animals. All this is revoltingly crude, a barbarism of the West, the source of which is to be found in Judaism. In philosophy it rests, despite all evidence to the contrary, on the assumed total difference between man and animal. We all know that such difference was expressed most definitely and strikingly by Descartes as a necessary consequence of his errors. Thus when the philosophy of Descartes, Leibniz, and Wolff built up rational psychology out of abstract concepts and constructed an immortal anima rationales, the natural claims of the animal world obviously stood up against this exclusive privilege, this patent of immortality of the human species, and nature, as always on such occasions, entered her silent protest. With an uneasy intellectual conscience, the philosophers then had to try to support rational psychology by means of the empirical. They were therefore concerned to open up a vast chasm, an immeasurable gulf between man and animal in order to represent them as fundamentally different, in spite of all evidence to the contrary. … In the end animals would be quite incapable of distinguishing themselves from the external world and would have no consciousness of themselves, no ego! To answer such absurd statements, we can point simply to the boundless egoism inherent in every animal, even the smallest and lowest, which shows clearly enough how very conscious they are of their ego in face of the world or the non-ego. If any Cartesian were to find himself clawed by a tiger, he would become aware in the clearest possible manner of the sharp distinction such a beast draws between its ego and the non-ego. In keeping with such sophisms of philosophers, we find a popular peculiarity in many languages, especially German, of giving animals special words of their own for eating, drinking, pregnancy, parturition, dying, and their bodies, so that we need not use the same words which describe those acts among human beings: and thus we conceal under a diversity or words the perfect and complete identity of the thing. Since the ancient languages did not recognize any such duplication, but rather frankly and openly denoted the same thing by the same word, that miserable artifice is undoubtedly the work of European priests and parsons. In their profanity these men think they cannot go far enough in disavowing and reviling the eternal essence that lives in all animals, and thus have laid the foundation of that harshness and cruelty to animals which is customary in Europe, but which no native of the Asiatic uplands can look at without righteous horror. In the English language we do not meet with this contemptible trick, doubtless because the Saxons, when they conquered England, were not yet Christians. On the other hand, we do find an analogy to it in the strange fact that in English all animals are of the neuter gender and so are represented by the pronoun “it,” just as if they were inanimate things. The effect of this artifice is quite revolting, especially in the case of primates, such as dogs, monkeys, and the like; it is unmistakably a priestly trick for the purpose of reducing animals to the level of things. The ancient Egyptians, whose whole life was dedicated to religious purposes, put the mummies of the ibis, crocodile, and so on, in the same vault with those of human beings. In Europe, however, it is an abomination and a crime for a faithful dog to be buried beside the resting place of his master, though at times, from a faithfulness and attachment not to be found among the human race, he there awaited his own death. Nothing leads more definitely to a recognition of the identity of the essential nature in animal and human phenomena than a study of zoology and anatomy. What, then, are we to say when in these days  a bigoted and canting zootomist has the audacity to emphasize an absolute and radical difference between man and animal, and goes so far as to attack and disparage honest zoologists who keep aloof from all priestly guile, toadyism, and hypocrisy, and pursue their course under the guidance of nature and truth? One must be really quite blind or totally chloroformed by the factor Judaicus not to recognize that the essential or principal thing in the animal and man is the same, and that what distinguishes the one from the other is not to be found in the primary and original principle, in the archaeus, in the inner nature, in the kernel of the two phenomena, such kernel being in both alike the will of the individual; but only in the secondary, in the intellect, in the degree of the cognitive faculty. In man this degree is incomparably higher through the addition of the faculty of abstract knowledge, called reason. Yet this superiority is traceable only to a greater cerebral development, and hence to the somatic difference of a single part, the brain, and in particular, its quantity. On the other hand, the similarity between animal and man is incomparably greater, both psychically and somatically. And so we must remind the Western, Judaized despiser of animals and idolater of the faculty of reason that, just as he was suckled by his mother, so too was the dog by his. Even Kant fell into this mistake of his contemporaries and countrymen; this I have already censured. The morality of Christianity has no consideration for animals, a defect that is better admitted than perpetuated. . .
Since compassion for animals is so intimately associated with goodness of character, it may be confidently asserted that whoever is cruel to animals cannot be a good man. This compassion also appears to have sprung from the same source as the virtue that is shown to human beings has. Thus, for example, persons of delicate feelings, on realizing that in a bad mood, in anger, or under the influence of wine, they unnecessarily or excessively, or beyond propriety, ill-treated their dog, horse, or monkey—these people will feel the same remorse, the same dissatisfaction with themselves as is felt when they recall a wrong done to human beings, where it is called the voice of reproving conscience.
 Kant’s first formulation of the supreme principle of morality reads: “Act so that maxima of your action may be adopted as a universal law.” His second formulation (the one Schopenhauer attacks) reads: “Act so as to treat humanity, both in thine own person and in the person of every other, always as an end, never merely as a means.
Texto de autoria do filósofo Arthur Schopenhauer em “On the Basis of Morality”, traduzido por E. F. J. Payne, publicado em 1840.