On page 241, Mr. Spencer deals with the question of the destructibility of matter: “The annihilation of matter is unthinkable for the same reason that the creation of matter is unthinkable.” (P. 54): “Matter in its ultimate nature is as absolutely incomprehensible as space and time.” The nature of matter is unthinkable, its creation or destructibility is unthinkable, and in this style of reasoning we can add that its indestructibility is likewise unthinkable; in fact the argument concerning self-existence will apply here. (P. 31): “Self-existence necessarily means existence without a beginning; and to form a conception of self-existence is to form a conception of existence without a beginning. Now by no mental effort can we do this. To conceive existence through infinite past time, implies the conception of infinite past time, which is an impossibility.” Thus, too, we might argue in a strain identical; indestructibility implies existence through infinite future time, but by no mental effort can infinite time be conceived. And thus, too, we prove and disprove the persistence of force and motion. When occasion requires, the ever-convenient argument of “inconceivability” enters. It reminds one of Sir Wm. Hamilton’s “imbecility” upon which are based “sundry of the most important phenomena of intelligence,” among which he mentions the category of causality. If causality is founded upon imbecility, and all experience upon it, it follows that all empirical knowledge rests upon imbecility.
On page 247, our author asserts that the first law of motion “is in our day being merged in the more general one, that motion, like matter, is indestructible.” It is interesting to observe that this so-called “First law of motion” rests on no better basis than very crude reflection.
“When not influenced by external forces, a moving body will go on in a straight line with a uniform velocity,” is Spencer’s statement of it.
This abstract, supposed law has necessitated much scaffolding in Natural Philosophy that is otherwise entirely unnecessary; it contradicts the idea of momentum, and is thus refuted:
I. A body set in motion continues in motion after the impulse has ceased from without, for the reason that it retains momentum.
II. Momentum is the product of weight by velocity, and weight is the attraction of the body in question to another body external to it. If all bodies external to the moving body were entirely removed, the latter would have no weight, and hence the product of weight by velocity would be zero.
III. The “external influences” referred to in the so-called “law,” mean chiefly attraction. Since no body could have momentum except through weight, another name for attraction, it follows that all free motion has reference to another body, and hence is curvilinear; thus we are rid of that embarrassing “straight line motion” which gives so much trouble in mechanics. It has all to be reduced back again through various processes to curvilinear movement.
We come, finally, to consider the central point of this system:
THE CORRELATION OF FORCES.
Speaking of persistence of force, Mr. Spencer concedes (p. 252) that this doctrine is not demonstrable from experience. He says (p. 254): “Clearly the persistence of force is an ultimate truth of which no inductive proof is possible.” (P. 255): “By the persistence of force we really mean the persistence of some power which transcends our knowledge and conception.” (P. 257): “The indestructibility of matter and the continuity of motion we saw to be really corollaries from the impossibility of establishing in thought a relation between something and nothing.” (Thus what was established as a mental impotence is now made to have objective validity.) “Our inability to conceive matter and motion destroyed is our inability to suppress consciousness itself.” (P. 258): “Whoever alleges that the inability to conceive a beginning or end of the universe is a negative result of our mental structure, cannot deny that our consciousness of the universe as persistent is a positive result of our mental structure. And this persistence of the universe is the persistence of that unknown cause, power, or force, which is manifested to us through all phenomena.” This “positive result of our mental structure” is said to rest on our “inability to conceive the limitation of consciousness” which is “simply the obverse of our inability to put an end to the thinking subject while still continuing to think.” (P. 257): “To think of something becoming nothing, would involve that this substance of consciousness having just existed under a given form, should next assume no form, or should cease to be consciousness.”