Among those uncontrouleable Levellers of the World, Fate, or Fortune, (in the Profane Lexicon, and in the Christians undiscovered Providence) may passe for the first; Opinion, and Time (or the Grave) for the other two. The two first require the more serious inquiry into, for the universality of their Power (and yet generall unobservance of it) and usefulnesse of its Contemplation in the occurences of life; the third is not lesse usefull, but a more common Theme, and so needs the lesse Descant.
Source: wiktionary