Page:Of the conduct of the understanding (IA ofconductofunder00lock).pdf/51

Rh views to the understanding. If I propose these, it is not, as I said, to make every man a thorough mathematician or a deep algebraist: but yet I think the study of them is of infinite use, even to grown men; first, by experimentally convincing them that to make any one reason well it is not enough to have parts wherewith he is satisfied and that serve him well enough in his ordinary course. A man in those studies will see, that however good he may think his understanding, yet in many things, and those very visible, it may fail him. This would take off that presumption that most men have of themselves in this part, and they would not be so apt to think their minds wanted no helps to enlarge them, that there could be nothing added to the acuteness and penetration of their understandings.

Secondly, the study of mathematics would show them the necessity there is in reasoning, to separate all the distinct ideas, and see the habitudes that all those concerned in the present inquiry have to one another, and to lay by those which relate not to the proposition in hand, and wholly to leave them out of the reckoning. This is that which in other subjects besides quantity, is what is absolutely requisite to just reasoning, though in them it is not so easily observed nor so carefully practiced. In those parts of knowledge where it is thought demonstration has nothing to do, men reason as it were in the lump; and if, upon a summary and confused view, or upon a partial consideration, they can raise the appearance of a probability, they