Freedom of Thought?

Freedom of thought is often explicitly protected in constitutions and human rights documents, and even more often employed as a rallying cry against state tyranny. It is not so clear, however, just what freedom of thought is, what it would be to threaten it, and how, if at all, it differs from basic liberty or freedom. This essay seeks to analyze the idea of freedom of thought, to pose some skeptical questions about its alleged independent existence, and to ask, again with a skeptical mindset, what it is to protect it and why its protection should be so commonly valued.