Universe Quotes - page 87
Therefore, the inhabitants of other stars - of whatever sort these inhabitants might be – bear no comparative relationship to the inhabitants of the earth (istius mundi ). [That is true] even if, with respect to the goal of the universe, that entire region bears to this entire region a certain comparative relationship which is hidden to us - so that in this way the inhabitants of this earth or region bear, through the medium of the whole region, a certain mutual relationship to those other inhabitants. (By comparison, the particular parts of the fingers of a hand bear, through the medium of the hand, a comparative relationship to a food; and the particular parts of the foot [bear], through the medium of the foot, [a comparative relationship] to a hand - so that all [members] are comparatively related to the whole animal.) Hence, since the entire region is unknown to us, those inhabitants remain altogether unknown.
Nicholas of Cusa