Anthony Collins is known mostly as an eighteenth-century freethinker who contributed to ideas of rational religion and religious toleration, as a close friend of John Locke, and as a necessitarian and materialist who held a significant correspondence with Samuel Clarke. Yet, his political philosophy has rarely received serious attention, and he remains a neglected figure in the history of political thought. This article attempts to recover Collins as a philosopher who developed a complex political theory, by focusing on his conceptions (...) of liberty and authority. It shows that he conceptualised liberty, and liberty of thought in particular, both as non-interference and non-domination, namely, an absence of censorship as well as an absence of continuous tyranny over the minds of humankind. Then, it shows that Collins also developed a thorough idea of civil authority, according to which even religious liberties may depend in some cases on the discretion of the civil sovereign. Finally, this article suggests that Collins’s multi-layered theory continued to develop after his lifetime, and that he therefore had a prominent place in eighteenth-century debates of liberty and authority. (shrink)