Were a man, whom I know to be honest and opulent, and with whom I live in intimate friendship, to come into my house, where I am surrounded with my servants, I rest assured, that he is not to stab me before he leaves it, in order to rob me of my silver standish; and I no more suspect this event, than the falling of the house itself which is new, and solidly built and founded.--But he may have been seized with a sudden and unknown frenzy.--So may a sudden earthquake arise, and shake and tumble my house about my ears.

We can conceive a thinking being to have either many or few perceptions. Suppose the mind to be reduced even below the life of anoyster. Suppose it to have only one perception, as of thirst or hunger. Consider it in that situation. Do you conceive any thing but merely that perception? Have you any notion of self or substance? If not, the addition of other perceptions can never give you that notion.

Human Nature is the only science of man; and yet has been hitherto the most neglected.

To hate, to love, to think, to feel, to see; all this is nothing but to perceive.

While Newton seemed to draw off the veil from some of the mysteries of nature, he showed at the same time the imperfections of the mechanical philosophy; and thereby restored her ultimate secrets to that obscurity, in which they ever did and ever will remain.

We may conclude, therefore, that, in order to establish laws for the regulation of property, we must be acquainted with the nature and situation of man; must reject appearances, which may be false, though specious; and must search for those rules, which are, on the whole, most useful and beneficial.

The rules of morality are not the conclusion of our reason.