le for thought to believe in the disengaged existence of matter.
The matter to be, believed in is not disengaged from the perception,
consequently it cannot be believed to be disengaged from the perception.
But unless it be believed to be disengaged from the perception, it
cannot be believed to exist _per se_. In short, as we have already said,
the impossibility of complying with the _condition_ of the belief is the
ground on which the sceptic denies the _existence_ of the belief. But
the sceptic is himself debarred from producing these grounds. Why?
Because their exhibition would be tantamount to a rejection of the
principle which he has _accepted_ at the hands of the orthodox and
dogmatic psychologist. That principle is the analysis so often spoken
of--the separation, namely, of the perception of matter into perception
and matter _per se_. The sceptic accepts this analysis. His business is
simply to _accept_, not to discover or scrutinise principles. Having
accepted the analysis, he then denies that any belief attaches to the
existence of matter _per se_. In this he is quite right. But he cannot,
consistently with his calling, exhibit the ground of his denial; for
this ground is, as we have shown, the impossibility of performing the
analysis,--of effecting the requisite disengagement. But the sceptic has
accepted the analysis, has admitted the disengagement. He therefore
cannot now retract: and he has no wish to retract. His special
mission--his only object is to confound the principle which he has
accepted by means of the reaction of its consequence. The inevitable
consequence which ensues when the analysis of the perception of matter
is admitted is the extinction of all belief in the existence of matter.
The analysis gives us a kind of matter to believe in to which no belief
corresponds. The sceptic is content with pronouncing this to be the fact
without going into its reason. It is not his business to correct, by a
direct exposure, the error of the principle which the dogmatist lays
down, and which he accepts. The analysis is the psychologist's affair;
let _him_ look to it. Were the sceptic to make it his, he would emerge,
from the sceptical crisis, and pass into a new stage of speculation. He,
indeed, subverts it indirectly by a _reductio ad absurdum_. But he does
not _say_ that he subverts it--he leaves the orthodox proposer of the
principle to find that out.

Reid totally misconceived the nature of scepticism and