To preserve the freedom of the human mind, then, and freedom of the press, every spirit should be ready to devote itself to martyrdom; for as long as we may think as we will, and speak as we think, the condition of man will proceed in improvement.

Thomas Jefferson (1743–1826) American political philosopher, polymath, statesman, US President (1801–09)

Letter (1799-06-18) to William Green Mumford
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