feeling be embodied, if not in the same organs as the feeling when present? It is only in this way that its identity can be preserved; a feeling differently embodied would be a different feeling."[76] It is not plain from Professor Bain's text whether by the 'same parts' he means only the same parts _inside the brain_, or the same _peripheral_ parts also, as those occupied by the original feeling. The examples which he himself proceeds to give are almost all cases of imagination of _movement_, in which the peripheral organs are indeed affected, for actual movements of a weak sort are found to accompany the idea. This is what we should expect. All currents tend to run forward in the brain and discharge into the muscular system; and the idea of a movement tends to do this with peculiar facility. But the question remains: Do currents run _backward_, so that if the optical centres (for example) are excited by 'association' and a visual object is imagined, a current runs _down to the retina_ also, and excites that sympathetically with the higher tracts? In other words, _can peripheral sense-organs be excited from above, or only from without? Are they excited in imagination?_ Professor Bain's instances are almost silent as to this point. All he says is this: "We might think of a blow on the hand until the skin were actually irritated and inflamed. The attention very much directed to any part of the body, as the great toe, for instance, is apt to produce a distinct feeling in the part, which we account for only by supposing a revived nerve-current to flow there, making a sort of false sensation, an influence from within mimicking the influences from without in sensation proper.--(See the writings of Mr. Braid, of Manchester, on Hypnotism, etc.)" If I may judge from my own experience, all feelings of this sort are consecutive upon motor currents invading the skin and producing contraction of the muscles there, the muscles whose contraction gives 'goose-flesh' when it takes place on an extensive scale. I never get a _feeling_ in the skin, however strongly I _imagine_ it, until some actual change in the condition of the skin itself has occurred. The truth seems to be that the cases where peripheral sense-organs are directly excited in consequence of imagination are exceptional rarities, if they exist at all. _In common cases of imagination it would seem more natural to suppose that the seat of the process is purely cerebral, and that the sense-organ is left out._ Reasons for such a conclusion would be briefly these: 1) In imagination the _starting-point_ of the process must be in the brain. Now we know that currents usually flow one way in the nervous system; and for the peripheral sense-organs to be excited in these cases, the current would have to flow backward.