But, instead of following Berkeley in his deductions from the position thus laid down, Hume, as the preceding citation shows, fully adopted the conclusion to which all that we know of psychological physiology tends, that the origin of the elements of consciousness, no less than that of all its other states, is to be sought in bodily changes, the seat of which can only be placed in the brain.

And, as Locke had already done with less effect, he states and refutes the arguments commonly brought against the possibility of a causal connexion between the modes of motion of the cerebral substance and states of consciousness, with great clearness:-- "From these hypotheses concerning the _substance_ and _local conjunction_ of our perceptions we may pass to another, which is more intelligible than the former, and more important than the latter, viz.

concerning the _cause_ of our perceptions.

Matter and motion, 'tis commonly said in the schools, however varied, are still matter and motion, and produce only a difference in the position and situation of objects.

Divide a body as often as you please, 'tis still body.