A Man that is of Copernicus’s Opinion, that this Earth of ours is a Planet, carry’d round and enlighten’d by the Sun, like the rest of the Planets, cannot but sometimes think, that it’s not improbable that the rest of the Planets have their Dress and Furniture, and perhaps their Inhabitants too as well as this Earth of ours.

Christiaan Huygens (1629-1695) Dutch physicist, mathematician, astronomer, inventor

Cosmotheoros, Book 1 (1695; publ. 1698) [tr. Clarke (1722)]
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