PREFACE.

THE object of this treatise is to give a full and systematic account of two principal divisions of the science of mind,-the Senses and the Intellect. The remaining two divisions, comprising the Emotions and the Will, will be the subject of a future treatise.

While endeavouring to present in a methodical form all the important facts and doctrines bearing upon mind, considered as a branch of science, I have seen reason to adopt some new views, and to depart in a few instances from the most usual arrangement of the topics.

Conceiving that the time has now come when many of the striking discoveries of Physiologists relative to the nervous system should find a recognised place in the Science of Mind, I have devoted a separate chapter to the Physiology of the Brain and Nerves.

In treating of the Senses, besides recognising the so-called muscular sense as distinct from the five senses, I have thought proper to assign to Movement and the feelings of Movement a position preceding the Sensations of the senses; and have endeavoured to prove that the exercise of active energy originating in purely internal impulses, inde