Principles Of Human Knowledge - pg. 113

But whatever power I may have over my own thoughts, I find the ideas actually perceieved by sense have not a like dependence on my will. When in broad day-light 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.

The ideas of sense are more strong, lively, and distinct that those of the imagination ; they have likewise a streadiness, 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.
This gives us a sort of a foresight, which enables us to regulate our actions for the benefit of life. And without this we should be eternally at a loss : we coild not know how to act any thing that might procure us the least pleasure, or remove the least pain of sense. That food nourishes, sleep refreshes, and fire warms us ; that to sow in the seed-time is the way to reap in the harvest, and, in general, that to obtain such or such ends, such or such means are conducive, all this we know, not by discovering any necessary connexion between our ideas, but only by the observation of the settled laws of Nature, without which we should be all in uncertainty and confusion, and a grown man no more know how to manage himself in the affairs of life, than an infant just born.