Now since in so many Things they... agree, what can be more probable than that in others they agree too; and that the other Planets are as beautiful and as well stock'd with Inhabitants as the Earth? Or what shadow of Reason can there be why they should not?
Christiaan Huygens (1722). “The Celestial Worlds Discover'd, Or, Conjectures Concerning the Inhabitants, Plants and Productions of the Worlds in the Planets”, p.18
