To understand what time is aright, without which we never can comprehend infinity, insomuch as one is a portion of the other,––we ought seriously to sit down and consider what idea it is, we have of duration, so as to give a satisfactory account, how we came by it.––What is that to any body? quoth my uncle Toby. For if you will turn your eyes inwards upon your mind, continued my father, and observe attentively, you will perceive, brother, that whilst you and I are talking together, and thinking and smoaking our pipes: or whilst we receive successively ideas in our minds, we know that we do exist, and so we estimate the existence, or the continuation of the existence of ourselves, or any thing else commensurate to the succession of any ideas in our minds, the duration of ourselves, or any such other thing co-existing with our thinking,––and so according to that preconceived––You puzzle me to death, cried my uncle Toby.
––'Tis owing to this, replied my father, that in our computations of time, we are so used to minutes, hours, weeks, and months,–and of clocks (I wish there was not a clock in the kingdom) to measure out their several portions to us, and to those who belong to us,–that 'twill be well, if in time to come, the succession of our ideas be of any use or service to us at all.

Laurence Sterne, The Life and Opinions of Tristram Shandy (Penguin Books, 1988) p. 200