Meditations, Book III, Section 10

Meditations, Book III, Section 10:

Use thine opinative faculty with all honour and respect, for in her indeed is all: that thy opinion do not beget in thy understanding anything contrary to either nature, or the proper constitution of a rational creature. The end and object of a rational constitution is, to do nothing rashly, to be kindly affected towards men, and in all things willingly to submit unto the gods. Casting therefore all other things aside, keep thyself to these few, and remember withal that no man properly can be said to live more than that which is now present, which is but a moment of time. Whatsoever is besides either is already past, or uncertain. The time therefore that any man doth live, is but a little, and the place where he liveth, is but a very little corner of the earth, and the greatest fame that can remain of a man after his death, even that is but little, and that too, such as it is whilst it is, is by the succession of silly mortal men preserved, who likewise shall shortly die, and even whiles they live know not what in very deed they themselves are: and much less can know one, who long before is dead and gone. 

Meditations, Book II, Section 12

Meditations, Book II, Section 12:

If thou shouldst live three thousand, or as many as ten thousands of years, yet remember this, that man can part with no life properly, save with that little part of life, which he now lives: and that which he lives, is no other, than that which at every instant he parts with. That then which is longest of duration, and that which is shortest, come both to one effect. For although in regard of that which is already past there may be some inequality, yet that time which is now present and in being, is equal unto all men. And that being it which we part with whensoever we die, it doth manifestly appear, that it can be but a moment of time, that we then part with. For as for that which is either past or to come, a man cannot be said properly to part with it. For how should a man part with that which he hath not? These two things therefore thou must remember. First, that all things in the world from all eternity, by a perpetual revolution of the same times and things ever continued and renewed, are of one kind and nature; so that whether for a hundred or two hundred years only, or for an infinite space of time, a man see those things which are still the same, it can be no matter of great moment. And secondly, that that life which any the longest liver, or the shortest liver parts with, is for length and duration the very same, for that only which is present, is that, which either of them can lose, as being that only which they have; for that which he hath not, no man can truly be said to lose.