In thus considering them, the first important distinction which occurred to us, related to their _causes_, or immediate antecedents, as foreign to the mind, or as belonging to the mind itself; a distinction too striking to be neglected as a ground of primary division. Whatever that may be, which feels and thinks, it has been formed to be susceptible of certain changes of state, in consequence of the mere presence of external objects, or at least of changes produced in our mere bodily organs, which, themselves, may be considered as external to the mind; and it is susceptible of certain other changes of state, without any cause external to itself, one state of mind being the immediate result of a former state of mind, in consequence of those laws of succession of thoughts and feelings, which He, who created the immortal soul of man, as a faint shadow of His own eternal spirit, has established in the constitution of our mental frame. In conformity with this distinction, we made our first division of the phenomena of the mind, into its _external_ and _internal_ affections; the word _affection_ being used, by me, as the simplest term for expressing a mere change of state induced, in relation to the affecting cause, or the circumstances, whatever they may have been, by which the change was immediately preceded. The class of _internal affections_,--by far the more copious and various of the two,--we divided into two great orders, our _intellectual_ states of mind, and our _emotions_, words which are, perhaps, better understood, before any definition is attempted of them, than after it, but which are sufficiently intelligible without definition, and appear to exhaust completely the whole internal affections of the mind. We have sensations or perceptions of the objects that affect our bodily organs; these I term the sensitive or external affections of the mind; we remember objects--we imagine them in new situations--we compare their relations; these mere conceptions or notions of objects and their qualities, as elements of our general knowledge, are what I have termed the intellectual states of the mind; we are moved with certain lively feelings, on the consideration of what we thus perceive, or remember, or imagine, or compare, with feelings, for example, of beauty, or sublimity, or astonishment, or love, or hate, or hope, or fear; these, and various other vivid feelings, analogous to them, are our _emotions_. There is no portion of our consciousness, which does not appear to me to be included in one or other of these three divisions. To know all our sensitive states or affections,--all our intellectual states,--and all our emotions, is to know all the states or phenomena of the mind; “Unde animus scire incipiat, quibus inchoet orsa Principiis seriem rerum tenuemque catenam Mnemosyne; Ratio unde, rudi sub pectore tardum Augeat imperium, et primum mortalibus ægris _Ira, dolor, metus, et curæ_ nascantur inanes.”[60]