On the freedom of thought

From Cato's Letters #15 (Febuary 4, 1720) by John Trenchard and Thomas Gordon

Without freedom of thought, there can be no such thing as wisdom; and no such thing as publick liberty, without freedom of speech: Which is the right of every man, as far as by it he does not hurt and control the right of another; and this is the only check which it ought to suffer, the only bounds which it ought to know.

This sacred privilege is so essential to free government, that the security of property; and the freedom of speech, always go together; and in those wretched countries where a man can not call his tongue his own, he can scarce call any thing else his own. Whoever would overthrow the liberty of the nation, must begin by subduing the freedom of speech; a thing terrible to publick traitors.

See here for my previous commentary on the influence of Cato's Letters.