The uniform, constant and uninterrupted effort of every man to better his condition, the principle from which public and national, as well as private opulence is originally derived, is frequently powerful enough to maintain the natural progress of things toward improvement, in spite both of the extravagance of government, and of the greatest errors of administration. Like the unknown principle of animal life, it frequently restores health and vigour to the constitution, in spite, not only of the disease, but of the absurd prescriptions of the doctor.

--The Wealth of Nations, Book II Chapter III

Little else is requisite to carry a state to the highest degree of opulence from the lowest barbarism but peace, easy taxes, and a tolerable administration of justice: all the rest being brought about by the natural course of things.

--Lecture in 1755, quoted by Dugald Stewart

Consumption is the sole end and purpose of all production; and the interest of the producer ought to be attended to, only so far as it may be necessary for promoting that of the consumer.

--The Wealth of Nations, Book IV Chapter VIII

Man was made for action, and to promote by the exertion of his faculties such changes in the external circumstances both of himself and others, as may seem most favourable to the happiness of all.

--The Theory of Moral Sentiments, Part II Section III Chapter 3

Such is the delicacy of man alone, that no object is produced to his liking. He finds that in everything there is need for improvement. The whole industry of human life is employed not in procuring the supply of our three humble necessities, food, clothes and lodging, but in procuring the conveniences of it according to the nicety and delicacy of our tastes.

--Lectures on Justice, Policy, Revenue and Arms

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