If two or more instances of the phenomenon under investigation have only one circumstance in common, the circumstance in which alone all the instances agree is the cause (or effect) of the given phenomenon.

All that makes existence valuable to any one depends on the enforcement of restraints upon the actions of other people.

Everyone who receives the protection of society owes a return for the benefit.

The process of tracing regularity in any complicated, and at first sight confused, set of appearances, is necessarily tentative; we begin by making any supposition, even a false one, to see what consequences will follow from it ; and by observing how these differ from the real phenomena, we learn what corrections to make in our assumption.

In a world in which there is so much to interest, so much to enjoy, and so much also to correct and improve, everyone who has this moderate amount of moral and intellectual requisites is capable of an existence which may be called enviable; and unless such a person, through bad laws, or subjection to the will of others, is denied the liberty to use the sources of happiness within his reach, he will not fail to find the enviable existence

Political Economy as a branch of science is extremely modern; but the subject with which its enquiries are conversant has in all ages necessarily constituted one of the chief practical interests of mankind.

As for charity, it is a matter in which the immediate effect on the persons directly concerned, and the ultimate consequence to the general good, are apt to be at complete war with one another.