=The Neural Process in Imagination.=--Most medical writers assume that the cerebral activity on which imagination depends occupies a different _seat_ from that subserving sensation. It is, however, a simpler interpretation of the facts to suppose that _the same nerve-tracts are concerned in the two processes_. Our mental images are aroused always by way of association; some previous idea or sensation must have 'suggested' them. Association is surely due to currents from one cortical centre to another. Now all we need suppose is that these intra-cortical currents are unable to produce in the cells the strong explosions which currents from the sense-organs occasion, to account for the subjective difference between images and sensations, without supposing any difference in their local seat. To the strong degree of explosion corresponds the character of 'vividness' or sensible presence, in the object of thought; to the weak degree, that of 'faintness' or outward unreality. If we admit that sensation and imagination are due to the activity of the same parts of the cortex, we can see a very good teleological reason why they should correspond to discrete kinds of process in these centres, and why the process which gives the sense that the object is really there ought normally to be arousable only by currents entering from the periphery and not by currents from the neighboring cortical parts. We can see, in short, why _the sensational process_ OUGHT TO _be discontinuous with all normal ideational processes, however intense_. For, as Dr. Münsterberg justly observes, "Were there not this peculiar arrangement we should not distinguish reality and fantasy, our conduct would not be accommodated to the facts about us, but would be inappropriate and senseless, and we could not keep ourselves alive."