The foundations on which several duties are built, and the foundations of right and wrong from which they spring, are not perhaps easily to be let into the minds of grown men, not us'd to abstract their thoughts from common received opinions. Much less are children capable of reasonings from remote principles. They cannot conceive the force of long deductions. The reasons that move them must be obvious, and level to their thoughts, and such as may be felt and touched. But yet, if their age, temper, and inclination be consider'd, they will never want such motives as may be sufficient to convince them.

Sec. 81 - Some Thoughts Concerning Education (1693)