The order of the world can then be conceived as a “modifiable fatality.”[75] In the eyes of the greater number of present thinkers, says Comte, this formula will seem contradictory. This comes from old habits of mind which are not easily broken with. In the same way, as we have had a great deal of trouble in representing truth to ourselves otherwise than as immutable, so we are unwilling to conceive order otherwise than as necessary. During a long time the science of mathematics has been the only positive science. The idea of law formed itself in this science, that is to say according to the necessary relations which are demonstrated in it. It came to be afterwards transferred, just as it was, into the other orders of phenomena, as the positive spirit progressed. But orders of phenomena differ qualitatively from one another. All laws ought not to be conceived according to the single type of geometrical and algebraical laws. In order to obtain a complete idea of a natural law, we must not confine ourselves to the mathematical order, which is an “exception” in this respect. All the orders of phenomena must be considered. We then see that law must be defined “constancy in variety.”
In fact, “the normal type is never suited to any but a medium state, more ideal than real, around which effective existence ceaselessly oscillates, so long as the deviation does not go beyond the limits which are compatible with the duration of the system. Order, even isolated, is no more eternal than it is absolute.”[76] In this passage, Comte is speaking of astronomical order, but the same consideration applies to all the systems or groups of phenomena. Every law is necessarily something abstract. Being indispensable to the intelligibility of the real, every law allows prevision and science to exist. But it is not an adequate expression of this reality, which never remains identical with itself.
Comte goes so far as to say that our requirement of precision in the study of natural laws must not be pushed too far. For the laws which it has been possible to establish within certain degrees of approximation vanish if this approximation is pushed further. Not that the phenomena cease to be subject to laws; but these laws becoming too complex, escape us. For instance, it has been possible to establish with our thermometers the laws of the variation of temperature of a body under certain conditions. With very much more sensitive thermometers the variations becomes incessant and very complicated. The known laws disappear without our being in a condition to establish others.[77]
The order which positive science shows us in nature is then very far from being absolute. It is, to speak truly, the outcome of the combined activity of our mind and of things. We cannot separate what belongs to each of these two factors, but it appears from what has just been said that the mind plays a great part, that the external relations are far more contingent than suits our blind instinct of universal connection.”[78] Nevertheless the phenomena are not irreducible to order, since science and prevision remain possible. But this order, entirely relative in respect to our understanding is only established within certain limits. More powerful minds than ours would probably construct richer and more complex orders for themselves. For us, beyond a certain point of complexity our vision becomes confused and our logical requirements are no longer satisfied. Limits would thus seem to be placed upon scientific investigation, and these in the interest of science itself.
Finally we reach the last consequence of this theory founded upon experience, the principle of laws and the principle of the conditions of existence only insure a provisional order. Comte readily admits that it might not exist. “This order might become so irregular that it might even escape brains superior to ours. There is nothing to prevent us from imagining words outside our solar system, always given over to an inorganic and entirely disordered agitation, which would not even allow of a general law of gravitation.”[79] This is the very hypothesis formulated by John Stuart Mill, in almost similar terms, and in which a kind of reductio ad absurdum of his own theory was thought to be found. It is, however, compatible with the existence of a science which does not claim to possess an absolute value. Moreover Comte at once adds, “Still, even if order should be found to be particular to our world, in fact, it would be in no way accidental in it, since it is the first condition for human existence.” In virtue of the principle of the conditions of existence, the presence of a being such as man implies the whole of the laws which govern our world.
V.
The laws which for us constitute the order of the world are of two kinds. Some are established by the positive method in each order of phenomena separately considered; the astronomical laws, physical laws, chemical laws, etc. They belong to the domain of science properly so-called. The others are apprehended when the mind leaves the special point of view of science, and places itself at the universal point of view of philosophy. They are found again in the different orders of phenomena, whose relations they express without compromising their respective independence. They represent them severally connected, or, according to Comte’s expression, as convergent. Comte calls these last encyclopædic laws. They tend to realise the unity which the mind claims, not in pursuing the chimerical reduction of all laws to a supreme law, but in showing that the systems of irreducible laws are nevertheless harmonious among themselves.
Generally speaking, these laws have been known for a long time, but only as special laws of such and such an order of phenomena. It belongs to positive philosophy to give them their encyclopædic character, that is to say, to make them universal. For instance, d’Alembert’s principle is known in mechanics as a law which connects questions of movement with questions of equilibrium. Philosophy finds a similar law in biology: (physiological questions are correlated to anatomical questions); and also in sociology (“progress is the development of order”). It then formulates the encyclopædic law which generalises these three laws, that is, the principle of the conditions of existence.
Similarly the three great laws of mechanics, known under the name of the laws of Kepler, of Galileo and of Newton, must be universalised and become encyclopædic for they are applicable to all the orders of phenomena.[80] The law of Kepler, in the first place, expresses the spontaneous tendency of all natural phenomena to persevere indefinitely in their state, if no disturbing influence supervenes; a tendency whence are derived inertia in mechanics, habit in living bodies, and the conservative instinct in societies. The law of Galileo which reconciles every common movement with the various particular movements, applies to all the organic and inorganic phenomena. For, in any system, we can always ascertain the independence of the several active or passive mutual relations with regard to any action which is exactly common to the various parts, whatever may be their kind and degree. Finally the universal character of Newton’s law (reaction is equal to action), is evident at first sight. It is accidentally, not essentially, that these laws have at first been mechanical laws. They could have been equally attained by the study of biological or social phenomena. If the science of mechanics was the first to formulate them it is because it has for its object the less complicated phenomena.
A complete and rational system of encyclopædic laws would realise the “philosophia prima” which Bacon dimly foresaw. In the actual condition of the sciences this would probably be a rash undertaking. Comte attempted it in the fourth volume of the Politique positive.[81] One can hardly say that the trial was a decisive one. It is true that at that moment Comte was already entirely taken up with religious preoccupations.