The Use and End of Reason, is not the finding of the summe, and truth of one, or a few consequences, remote from the first definitions, and settled significations of names; but to begin at these; and proceed from one consequence to another. For there can be no certainty of the last Conclusion, without a certainty of all those Affirmations and Negations, on which it was grounded, and inferred. As when a master of a family, in taking an account, casteth up the summs of all the bills of expence, into one sum; and not regarding how each bill is summed up, by those that give them in account; nor what it is he payes for; he advantages himself no more, than if he allowed the account in grosse, trusting to every of the accountants skill and honesty: so also in Reasoning of all other things, he that takes up conclusions on the trust of Authors, and doth not fetch them from the first Items in every Reckoning, (which are the significations of names settled by definitions), loses his labour; and does not know any thing; but onely beleeveth.

(Thomas Hobbes, Leviathan, rev. student ed., ed. Richard Tuck, Cambridge Texts in the History of Political Thought, ed. Raymond Geuss and Quentin Skinner [Cambridge: Cambridge University Press, 1996], chap. 5, p. 33 [first published in 1651])