Even in our wildest dreams,--in which we imagine all things that are possible, and almost all things which are impossible; we never consider our joy or sorrow, as directly indicative of any thing separate from ourselves, and independent of us, “While o'er our limbs sleep's soft dominion spread, What tho' our soul fantastic measures trod, O'er fairy fields; or mourn'd along the gloom Of pathless woods; or down the craggy steep Hurl'd headlong, swam with pain the mantled pool; Or scaled the cliff,--or danced on hollow winds, With antic shapes, wild natives of the brain;” it was still only the cliff, the wood, the pool, which we considered as _external_: the _sorrow_ with which we mourned along our gloomy track, the _pain_ with which we swam the turbid water, the _horror_ which we felt at the antic shapes, with which we mingled in the ghostly dance, were felt to be wholly _in ourselves_, and constituted, while they lasted, the very feeling of our own existence.--The belief of an external world is, however, to come afterwards under our full examination:--It is sufficient, for the present, to know, that in the period after infancy, to which alone our memory extends, we are led, irresistibly, to believe in it; and that the belief of it, therefore, in whatever manner it may have originated in the imperfect perceptions of our infancy, is now, when those perceptions are mature, so completely beyond the power of argument to overcome, that it exists, as strongly, in those who reason against it, as in those who reason for it;--that the reference to a direct external cause, however, does not accompany _every_ feeling of our mind, but is confined to a certain number of that long succession of feelings, which forms the varied consciousness of our life,--and that the feelings, with respect to which this reference is made, are the class of sensations, which, when combined with this reference, have commonly been distinguished by the name of perceptions. That we have no perfect evidence of the external existence thus ascribed by us,--independently of our own irresistible belief of it, may be allowed to the sceptic; and the reasoning of Doctor Reid on the subject, as far as he proceeds beyond the assertion of this irresistible belief, and attempts, what has been commonly regarded as a confutation of the scepticism on this point,--by representing it as proceeding on a mistake, with respect to the nature of our ideas,--is _itself_, as we shall afterwards find, nugatory and fallacious. But still, notwithstanding the errors of philosophers with respect to it, the belief itself is, in the circumstances in which we now exist, so truly a part of our constitution, that to contend against it in argument would be to admit its validity, since it would be to suppose the existence of some one whom we are fairly undertaking to instruct or to confute.