#gabitaykoRefEd (Robert Spaemann)
From the possibility of doubting everything, it does not follow that it would be good to do that. The necessity of positing the reality of the living is not a theoretical compulsion but is itself a kind of moral evidence. Whoever loves a human, whoever has friends, cannot at the same time doubt the beloved's or the friend's existence. That person must hold the other's being alive as irreducible. And when I say one cannot doubt, I do not mean a physical or logical impossibility, but a moral and, therefore, absolute impossibility. Insofar as I doubt his reality, I do not merely bracket somewhat the reality of the friendship; rather, I destroy it. Friendship does not allow for an ontological abstinence, for an epoche. It implies an ontological affirmation. In the case of friendship, this affirmation is not a postulate but a necessary implication. But there, where the relationship to the other does not have the intensity of friendship but is defined by the claim of each to "respect," there the moral claim becomes a metaphysical postulate, becomes the postulate of recognizing the other as "real."
—Robert Spaemann