GraniteGrok

As the author of the post points out, conservatives can vary on the foundational ideas define what Conservatism.  I found these to be worthwhile (abridged from the original post):

Being neither a religion nor an ideology, the body of opinion termed conservatism possesses no Holy Writ and no Das Kapital to provide dogmata. So far as it is possible to determine what conservatives believe, the first principles of the conservative persuasion are derived from what leading conservative writers and public men have professed during the past two centuries. After some introductory remarks on this general theme, I will proceed to list ten such conservative principles.

• First, the conservative believes that there exists an enduring moral order. That order is made for man, and man is made for it: human nature is a constant, and moral truths are permanent...
• Second, the conservative adheres to custom, convention, and continuity. It is old custom that enables people to live together peaceably; the destroyers of custom demolish more than they know or desire. It is through convention—a word much abused in our time—that we contrive to avoid perpetual disputes about rights and duties: law at base is a body of conventions. Continuity is the means of linking generation to generation;...
• Third, conservatives believe in what may be called the principle of prescription. Conservatives sense that modern people are dwarfs on the shoulders of giants, able to see farther than their ancestors only because of the great stature of those who have preceded us in time. Therefore conservatives very often emphasize the importance of prescription—that is, of things established by immemorial usage, so that the mind of man runneth not to the contrary. There exist rights of which the chief sanction is their antiquity—including rights to property, often. Similarly, our morals are prescriptive in great part. Conservatives argue that we are unlikely, we moderns, to make any brave new discoveries in morals or politics or taste... 
• Fourth, conservatives are guided by their principle of prudence. Burke agrees with Plato that in the statesman, prudence is chief among virtues. Any public measure ought to be judged by its probable long-run consequences, not merely by temporary advantage or popularity. Liberals and radicals, the conservative says, are imprudent: for they dash at their objectives without giving much heed to the risk of new abuses worse than the evils they hope to sweep away...
• Fifth, conservatives pay attention to the principle of variety. They feel affection for the proliferating intricacy of long-established social institutions and modes of life, as distinguished from the narrowing uniformity and deadening egalitarianism of radical systems...
• Sixth, conservatives are chastened by their principle of imperfectability. Human nature suffers irremediably from certain grave faults, the conservatives know. Man being imperfect, no perfect social order ever can be created. Because of human restlessness, mankind would grow rebellious under any utopian domination, and would break out once more in violent discontent—or else expire of boredom...
• Seventh, conservatives are persuaded that freedom and property are closely linked. Separate property from private possession, and Leviathan becomes master of all. Upon the foundation of private property, great civilizations are built. The more widespread is the possession of private property, the more stable and productive is a commonwealth...
• Eighth, conservatives uphold voluntary community, quite as they oppose involuntary collectivism. Although Americans have been attached strongly to privacy and private rights, they also have been a people conspicuous for a successful spirit of community. In a genuine community, the decisions most directly affecting the lives of citizens are made locally and voluntarily. Some of these functions are carried out by local political bodies, others by private associations: so long as they are kept local, and are marked by the general agreement of those affected, they constitute healthy community. But when these functions pass by default or usurpation to centralized authority, then community is in serious danger...
• Ninth, the conservative perceives the need for prudent restraints upon power and upon human passions. Politically speaking, power is the ability to do as one likes, regardless of the wills of one’s fellows. A state in which an individual or a small group are able to dominate the wills of their fellows without check is a despotism, whether it is called monarchical or aristocratic or democratic...It is characteristic of the radical that he thinks of power as a force for good—so long as the power falls into his hands...
• Tenth, the thinking conservative understands that permanence and change must be recognized and reconciled in a vigorous society. The conservative is not opposed to social improvement, although he doubts whether there is any such force as a mystical Progress, with a Roman P, at work in the world.
  

(H/T: RedState)