Parents wonder why the streams are bitter, when they themselves poison the fountain. - John Locke

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.

We are all short sighted, and very often see but one side of a matter; our views are not extended to all that has a connection with it. From this defect I think no man is free. We see but in part, and we know but in part, and therefore it is no wonder we conclude not right from our partial views. This might instruct the proudest esteemer of his own parts, how useful it is to talk and consult with others, even such as come short of him in capacity, quickness and penetration: for since no one sees all, and we generally have different prospects of the same thing, according to our different, as I may say, positions to it, it is not incongruous to think nor beneath any man to try, whether another may not have notions of things which have escaped him, and which his reason would make use of if they came into his mind.

One or two particulars may suggest hints of enquiry, and they do well who take those hints; but if they turn them into conclusions, and make them presently general rules, they are forward indeed, but it is only to impose on themselves by propositions assumed for truths without sufficient warrant.