Consequently, while in the a priori doctrines the possibility of all science rests upon the principle of laws, in Comte’s doctrine, on the contrary, it is the progress of positive science which by degrees founds the principle, and which finally brings it to the universal form in which we find it to-day. Until the creation of sociology, this principle did not yet possess an effective universality, since the moral and social phenomena were not conceived as subject to invariable laws. But when the last conquest of the positive spirit is once accomplished, “this great principle at once acquires a decisive fulness, and may be formulated as applying universally to all phenomena.” Undoubtedly, in each order, we have only established for a few what henceforth we affirm for all phenomena without previous verification. But we think that laws, unknown to us, nevertheless exist. In this we yield to an “irresistible analogy,” which has never been proved to be false.
Thus, “the most fundamental dogma of the whole of positive philosophy, that is to say, the subjection of all real phenomena to invariable laws, only results with certainty from an immense induction, without really being deducible from any notion whatever.”[53] This immense induction is a progressive sum of inductions which have taken place successively in each category of phenomena. It would not be absurd, strictly speaking, that a certain category should not be submitted, like the others to invariable laws. But, since sociology has been founded, we know that all are in fact so subjected.
The laws are known to us, sometimes by experience, sometimes by reasoning. This diversity of origin in no way influences either the certainty or the philosophical dignity of the laws. Each of the six fundamental sciences gives examples of these two distinct modes of advance which mutually complete each other. “There is not less genius in the discovery of Kepler than in that of Newton. The initial laws of mechanics and even of geometry rest solely upon observation. The logical perfection consists in confirming by one of these ways what must have been found by the other. But one of the two suffices when all the conditions required by the method are fulfilled.”[54] How should the laws obtained by induction be regarded as less certain than the laws obtained by deduction, since the principle of laws itself rests upon an induction?
III.
In proportion as the several orders of phenomena are conceived as governed by invariable laws, the belief in final causes becomes weaker and tends to disappear. The final causes are imagined by the mind to explain certain combinations of natural phenomena. When the laws of these phenomena are known, this explanation becomes useless, it ceases to have currency. It shares the fate of the whole of theological and metaphysical philosophy, of which it is a part.
The doctrine of final causes is generally regarded as a constituent principle of religious systems. A special argument in favour of the existence of God has even been drawn from it. Comte remarks that it is more probably a consequence of these systems. So long as man believes in the continual action of the gods, or of God, in nature, he does not need the consideration of final causes upon which to found his belief. He does not even dream of it. Later on only, when the religious conception of the world has become weaker, when God has so far withdrawn from the world as to be no longer anything but a sovereign who reigns, but does not govern, then the need is felt to demonstrate His existence, and the order of nature becomes an argument. The consideration of final causes from this point of view is a symptom of the weakening of the theological spirit; it is thus pre-eminently a metaphysical doctrine.
Whatever may be the case, experience witnesses against it. Positive science does not lay down that the world must be conceived as the work of an all-powerful intelligence. For instance, the scientific knowledge of our solar system has shown in the most obvious manner, and in various ways, that the elements of this system were certainly not disposed in the most advantageous manner, and that science allowed us to conceive of a better arrangement.[55] Astronomers may admire a natural finality in the organisation of animals; but the anatomists who know all its imperfections, fall back upon the arrangements of the stars. In what concerns animals, a blind admiration wonders even at evidently detrimental complications: it is the case with the eye, with the bladder, etc.[56] But “it is an almost universal disposition of physiologists to draw, even from their ignorance, as many motives for the admiration of the profound wisdom of a mechanism which they declare they cannot understand.”
In truth, the natural order, so much extolled, is extremely imperfect, and we can without difficulty conceive a better one. The human works, says Comte, from the most simple mechanical appliances to the most sublime political constructions, are generally far superior either in expediency, or in simplicity, to everything that the most perfect natural economy can offer us.[57] Our geometers and our physicians “sufficiently prepared” would do far better than nature, if they dared “to take the direct conception of a new animal mechanism as the object of an intellectual exercise.” This idea of artificial organisms pleases Comte and he often returns to it. He considers that fictions of this kind may be useful in biology to intercalate intermediaries between the several known organisms, in such a manner as to facilitate comparison in making the biological series more homogeneous and continuous.[58] In fact this is what Broca attempted to do, when he endeavoured to connect man with the other primates by hypothetical anthropoids. Quite recently M. Delage has made use of a similar fiction in his Traité de Zoologie.
Comte seldom misses an opportunity of smiling at the stupid admiration of those who believe that nature has done everything “for the best,” or that everything in it has been ordered by a providential wisdom. But we can surprise him also in the very act of admiration; not doubtless on the subject of astronomical or biological phenomena, but in the chapter which lies nearest to his heart, that of social facts. He writes, “we cannot experience too much respect and admiration when we see this universal natural disposition which is the primary basis of all society....”[59] and elsewhere: “Can one really conceive, in the whole of natural phenomena, a more marvellous spectacle than this regular and continuous convergence of an immensity of individuals....”[60]
However, there is not here a contradiction. In reality, although Comte says that the consideration of final causes must be accepted altogether, or rejected altogether, he does not himself reject it as entirely as he seems at first to do.