By the streets of "by and by" one arrives at the house of "never." Don Quixote

And are not the temperate exactly in the same case? They are temperate because they are intemperate—which may seem to be a contradiction, but is nevertheless the sort of thing which happens with this foolish temperance. For there are pleasures which they must have, and are afraid of losing; and therefore they abstain from one class of pleasures because they are overcome by another: and whereas intemperance is defined as "being under the domination of pleasure," they overcome only because they are overcome by pleasure. The Trials Of Socrates

Make hay while the sun shines. Don Quixote

One must pay dearly for immortality; one has to die several times while still alive. Ecce Homo