WE cannot define either motion or matter, but we have certain rough and
ready ideas concerning them which, right or wrong, we must make the best
of without more words, for the chances are ten to one that attempted
definition will fuzz more than it will clear.
Roughly, matter and motion are functions one of another, as are mind and
matter; they are essentially concomitant with one another, and neither
can vary but the other varies also. You cannot have a thing “matter” by
itself which shall have no motion in it, nor yet a thing “motion” by
itself which shall exist apart from matter; you must have both or
neither. You can have matter moving much, or little, and in all
conceivable ways; but you cannot have matter without any motion more than
you can have motion without any matter that is moving.
Its states, its behaviour under varying circumstances, that is to say the
characteristics of its motions, are all that we can cognise in respect of
matter. We recognise certain varying states or conditions of matter and
give one state one name, and another another, as though it were a man or
a dog; but it is the state not the matter that we cognise, just as it is
the man’s moods and outward semblance that we alone note, while knowing
nothing of the man. Of matter in its ultimate essence and apart from
motion we know nothing whatever. As far as we are concerned there is no
such thing: it has no existence: for _de non apparentibus et non
existentibus eadem est ratio_.
It is a mistake, therefore, to speak about an “eternal unchangeable
underlying substance” as I am afraid I did in the last pages of _Luck or
Cunning_? but I am not going to be at the trouble of seeing. For, if the
substance is eternal and unknowable and unchangeable, it is tantamount to
nothing. Nothing can be nearer non-existence than eternal unknowableness
and unchangeableness.
If, on the other hand, the substance changes, then it is not unknowable,
or uncognisable, for by cognising its changes we cognise it. Changes are
the only things that we can cognise. Besides, we cannot have substance
changing without condition changing, and if we could we might as well
ignore condition. Does it not seem as though, since the motions or
states are all that we cognise, they should be all that we need take
account of? Change of condition is change of substance. Then what do we
want with substance? Why have two ideas when one will do?
I suppose it has all come about because there are so many tables and
chairs and stones that appear not to be moving, and this gave us the idea
of a solid substance without any motion in it.
How would it be to start with motion approximately patent, and motion
approximately latent (absolute patency and absolute latency being
unattainable), and lay down that motion latent as motion becomes patent
as substance, or matter of chair-and-table order; and that when patent as
motion it is latent as matter and substance?
I am only just recovering from severe influenza and have no doubt I have
been writing nonsense.