he has ideas of two principal powers, marked by the names will and understanding, distinct from each other as well as from a third idea of Substance or Being in general, with a relative notion of its supporting or being the subject of the aforesaid powers—­which is signified by the name soul or spirit.  This is what some hold; but, so far as I can see, the words will [Note:  “Understanding, mind.”—­Edit 1710.], Soul, spirit, do not stand for different ideas, or, in truth, for any idea at all, but for something which is very different from ideas, and which, being an agent, cannot be like unto, or represented by, any idea whatsoever.  Though it must be owned at the same time that we have some notion of soul, spirit, and the operations of the mind:  such as willing, loving, hating—­inasmuch as we know or understand the meaning of these words.

28.  I find I can excite ideas in my mind at pleasure, and vary and shift the scene as oft as I think fit.  It is no more than willing, and straightway this or that idea arises in my fancy; and by the same power it is obliterated and makes way for another.  This making and unmaking of ideas doth very properly denominate the mind active.  Thus much is certain and grounded on experience; but when we think of unthinking agents or of exciting ideas exclusive of volition, we only amuse ourselves with words.

29.  Ideas of sensation differ from those of reflection or memory.—­But, whatever power I may have over my own thoughts, I find the ideas actually perceived by Sense have not a like dependence on my will.  When in broad daylight I open my eyes, it is not in my power to choose whether I shall see or no, or to determine what particular objects shall present themselves to my view; and so likewise as to the hearing and other senses; the ideas imprinted on them are not creatures of my will.  There is therefore some other will or spirit that produces them.

30.  Laws of nature.—­The ideas of Sense are more strong, lively, and distinct than those of the imagination; they have likewise a steadiness, order, and coherence, and are not excited at random, as those which are the effects of human wills often are, but in a regular train or series, the admirable connexion whereof sufficiently testifies the wisdom and benevolence of its Author.  Now the set rules or established methods wherein the mind we depend on excites in us the ideas of sense, are called the laws of nature; and these we learn by experience, which teaches us that such and such ideas are attended with such and such other ideas, in the ordinary course of things.