"That particular and determinate _degree of velocity_ in a wheel, whereby it turns once round precisely in twelve hours, is that which you call _the power of a clock_ to show the time of the day; and because such a determinate velocity of motion is _made use of by us_ for the measure of time, is it therefore really a new quality or power distinct from the motion itself ?" The same answer is equally applicable to all the other examples, and it may be stated generally as amounting to this, that "it is absolutely false in fact, and impossible in the nature of things, that any power whatsoever should inhere or reside in any system or composition of matter, different from the powers residing in the single parts."[173] The two great difficulties which adhere to the theory of Materialism, and which must ever prove insurmountable, are these: first, to account for the power of thinking by means of material atoms, which are individually destitute of it; and secondly, to account for the unity and continuity of human consciousness by means of material atoms which are constantly undergoing flux and mutation.

For the first end, recourse has been had to the theory which ascribes the power of thinking, not to the particles of matter, but to their order, arrangement, or organization; and for the second, the continuous sense of personal identity is supposed to be sufficiently accounted for by supposing that, as the particles which compose the brain are changed, the retiring atoms leave their share of the general consciousness as a legacy to their successors.

And both these expedients for surmounting the difficulty are exquisitely caricatured in the "Memoirs of Martinus Scriblerus," in a chapter which is justly described as "an inimitable ridicule on Collins' argument against Clarke, to prove the soul only a quality." The Society of Freethinkers, addressing Martinus, propose to send him an answer to the ill-grounded sophisms of their opponents, and likewise "an easy mechanical explanation of perception or thinking."-- "One of their chief arguments," say they, "is that self-consciousness cannot inhere in any system of matter, because all matter is made up of several distinct beings which never can make up one individual thinking being.

This is easily answered by a familiar instance.

In every _jack_ there is a _meat-roasting_ quality, which neither resides in the fly, nor in the weight, nor in any particular wheel, of the jack, but is the result of the whole composition....