How can you reconcile free markets & social conservatism?

Many rightfully wonder how someone who believes in economic freedom and free markets can consistently defend more conservative social policies, such as opposing gay marriage. I used to think that there was no underlying vision that could unite social conservatism and economic libertatianism. And yet I know understand that the coincidence of these views is actually a deep rooted vision that stretches back at least to Edmund Burke. It is what Thomas Sowell calls the "constrained" vision, as opposed to the "unconstrained" vision. Sowell's "A Conflict of Visions: Ideological Origins of Political Struggles," first published in the late 1980s, is perhaps his best book. The sides don't map directly to the familiar left/right spectrum and Sowell is not, in this book at least, making a case for either vision. But understanding these visions, and the impact they have had for centuries on political struggles, is perhaps the best way to understand what is at the root of today's differing political perspectives. You will be amazed at how many of the political debates of today have actually been debated for centuries and how the different "visions" explain much about how we form our beliefs. I believe it is a must read for anyone who wants to be considered literate in political science.