But the monopoly should not be granted. The name Materialism is quite convenient for it, just as Idealism is for the opposing system; and if either of these titles is objected to by the upholders of either system, as apparently too thorough-going and exclusive, whereas only a tendency in one or other direction is to be indicated, then the longer but more descriptive titles of Idealistic-monism and Materialistic-monism respectively should be employed. But neither of these compromises seems necessary to connote the position of Professor Haeckel.
The truth is that all philosophy aims at being monistic; it is bound to aim at unification, however difficult of attainment; and a philosopher who abandoned the quest, and contented himself with a permanent antinomy—a universe compounded of two or more irreconcilable and entirely disparate and disconnected agencies—would be held to be throwing up his brief as a philosopher and taking refuge in a kind of permanent Manichæism, which experience has shown to be an untenable and ultimately unthinkable position.
An attempt at Monism is therefore common to all philosophers, whether professional or amateur; and the only question at issue is what sort of Monism are you aiming at, what sort of solution of the universe have you to offer, what can you hold out to us as a simple satisfactory comprehensive scheme of existence?
In order to estimate the value of Professor Haeckel's scheme of the universe, it is not necessary to appeal to philosophers: it is sufficient to meet him on scientific ground, and to show that in his effort to simplify and unify he has under-estimated some classes of fact and has stretched scientific theory into regions of guess-work and hypothesis, where it loses touch with real science altogether. The facts which he chooses gratuitously to deny, and the facts which he chooses vigorously to emphasise, are arbitrarily selected by him according as they will or will not fit into his philosophic scheme. The scheme itself is no new one, and almost certainly contains elements of truth. Some day far hence, when it is possible properly to formulate it, a system of Monism may be devised which shall contain the whole truth. At present the scheme formulated by Professor Haeckel must to philosophers appear rudimentary and antiquated, while to men of science it appears gratuitous, hypothetical, in some places erroneous, and altogether unconvincing.
Before everything a philosopher should aim at being all-inclusive, before everything a man of science should aim at being definite, clear, and accurate. An attempt at combination is an ambitious attempt, which may legitimately be made, but which it appears is hardly as yet given to man to make successfully. Attempts at an all-embracing scheme, which shall be both truly philosophic and truly scientific, must for the present be mistrusted, and the mistrust should extend especially to their negative side. Positive contributions, either to fact or to system, may be real and should be welcome; but negative or destructive criticism, the eschewing and throwing away of any part of human experience, because it is inconsistent with a premature and ill-considered monistic or any other system, should be regarded with deep suspicion; and the promulgation of any such negative and destructive scheme, especially in association with free and easy dogmatism, should automatically excite mistrust and repulsion.
There are things which cannot yet be fitted in as part of a coherent scheme of scientific knowledge—at present they appear like fragments of another order of things; and if they are to be forced into the scientific framework, like portions of a "puzzle-map," before their true place has been discovered, a quantity of substantial fact must be disarranged, dislocated, and thrown away. A premature and cheap Monism is therefore worse than none at all.
CHAPTER II
"THE LAW OF SUBSTANCE"
I shall now endeavour to exhibit the way in which Professor Haeckel proceeds to expound his views, and for that purpose shall extract certain sentences from his work, The Riddle of the Universe; giving references to the sixpenny translation, now so widely circulated in England, in order that they may be referred to in their context with ease. To scientific men the exaggeration of statement will in many cases be immediately obvious; but in the present state of general education it will often be necessary to append a few comments, indicating, as briefly as possible, wherein the statement is in excess of ascertained fact, however interesting as a guess or speculation; wherefore it must be considered illegitimate as a weapon wherewith to attack other systems, so far as they too are equally entitled to be considered reasonable guesses at truth.
The central scientific doctrines upon which Professor Haeckel's philosophy is founded appear to be two—one physical, the other biological. The physical doctrine is what he calls "the Law of Substance"—a kind of combination of the conservation of matter and the conservation of energy: a law to which he attaches extraordinary importance, and from which he draws momentous conclusions. Ultimately he seems to regard this law as almost axiomatic, in the sense that a philosopher who has properly grasped it is unable to conceive the negative. A few extracts will suffice to show the remarkable importance which he attaches to this law:—
"All the particular advances of physics and chemistry yield in theoretical importance to the discovery of the great law which brings them to one common focus, the 'law of substance.' As this fundamental cosmic law establishes the eternal persistence of matter and force, their unvarying constancy throughout the entire universe, it has become the pole-star that guides our monistic philosophy through the mighty labyrinth to a solution of the world-problem" (p. 2).