The use and end of reason is not the finding of the sum 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 sums of all the bills of expense into one sum, and not regarding how each bill is summed up by those that give them in account, nor what it is he pays for, he advantages himself no more than if he allowed the account in gross, 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 anything, but only believeth.