Whatsoever made his business to miscarry,it leas not want of right thought and judgment in himself;he sees no such defect in himself,but is satisfied that he carries on his designs well enough by his own reasoning,or at least should have done,had it not been for unlucky traverses not in his power.Thus being content with this short and very imperfect use of his understanding,he never troubles himself to seek out methods of improving his mind,and lives all his life without any notion of close reasoning in a continued connection of a long train of consequences from sure foundations,such as is requisite for the making out and clearing most of the speculative truths most men own to believe and are most concerned in.Not to mention here what I shall have occasion to insist on by and by more fully,viz.,that in many cases it is not one series of consequences will serve the turn,but manor different and opposite deductions must be examined and laid together before a man can come to make a right judgment of the point in question.What then can be expected from men that neither see the want of any such kind of reasoning as this nor,if they do,know they how to set about it or could perform it?You may as well set a countryman who scarce knows the figures and never cast up a sum of three particulars to state a merchant's long account and find the true balance of it.
What then should be done in the case?I answer,we should always remember what I said above,that the faculties of our souls are improved and made useful to us just after the same manner as our bodies are.Would you have a man write or paint,dance or fence well,or perform any other manual operation dexterously and with ease,let him have never so much vigor and activity,suppleness and address naturally,yet nobody expects this from him unless he has been used to it and has employed time and pains in fashioning and forming his hand or outward parts to these motions.Just so it is in the mind;would you have a man reason well,you must use him to it betimes,exercise his mind in observing the connection of ideas and following them in train.Nothing does this better than mathematics,which therefore I think should be taught all those who have the time and opportunity,not so much to make them mathematicians as to make them reasonable creatures;for though we all call ourselves so,because we are born to it if we please,yet we may truly say nature gives us but the seeds of it;we are born to be,if is e please,rational creatures,but it is use and exercise only that makes us so,and we are indeed so no further than industry and application has carried us.And therefore in ways of reasoning which men have not been used to,he that will observe the conclusions they take up must be satisfied they are not all rational.
This has been the less taken notice of,because everyone in his private affairs uses some sort of reasoning or other,enough to denominate him reasonable.But the mistake is that he that is found reasonable in one thing is concluded to be so in all,and to think or say otherwise is thought so unjust an affront and so senseless a censure that nobody ventures to do it.It looks like the degradation of a man below the dignity of his nature.It is true,that he that reasons well in any one thing has a mind naturally capable of reasoning well in others,and to the same degree of strength and clearness,and possibly much greater,had his understanding been so employed.But it is as true that he who can reason well today about one sort of matters cannot at all reason today about others,though perhaps a year hence he may.But wherever a man's rational faculty fails him and will not serve him to reason,there we cannot say he is rational,how capable however he may be by time and exercise to become so.
Try in men of holy and mean education,who have never elevated their thoughts above the spade and the plough nor looked beyond the ordinary drudgery of a day-laborer.Take the thoughts of such an one,used for many years to one tract,out of that narrow compass he has been all his life confined to,you will find him no more capable of reasoning than almost a perfect natural.
Some one or two rules on which their conclusions immediately depend you will find in most men have governed all their thoughts;these,true or false,have been the maxims they have been guided by.Take these from them,and they are perfectly at a loss,their compass and polestar then are gone and their understanding is perfectly at a nonplus;and therefore they either immediately return to their old maxims again as the foundations of all truth to them,notwithstanding all that can be said to show their weakness,or,if they give them up to their reasons,they with them give up all truth and further enquiry and think there is no such thing as certainty.For if you would enlarge their thoughts and settle them upon more remote and surer principles,they either cannot easily apprehend them,or,if they can,know not what use to make of them;for long deductions from remote principles is what they have not been used to and cannot manage.
What then,can grown men never be improved or enlarged in their understandings?I say not so,but this I think I may say,that it will not be done without industry and application,which will require more time and pains than grown men,settled in their course of life,will allow to it,and therefore very seldom is done.And this very capacity of attaining it by use and exercise only brings us back to that which I laid down before,that it is only practice that improves our minds as w ell as bodies,and we must expect nothing from our understandings any further than they are perfected by habits.
The Americans are not all born with worse understandings than the Europeans,though eve see none of them have such reaches in the arts and sciences.And among the children of a poor countryman the lucky chance of education and getting into the world gives one infinitely the superiority in parts over the rest,who,continuing at home,had continued also just of the same size with his brethren.
He that has to do with young scholars,especially in mathematics,may perceive how their minds open by degrees,and how it is exercise alone that opens them.
Sometimes they would stick a long time at a part of a demonstration,not for want of will or application,but really for want of perceiving the connection of two ideas that,to one whose understanding is more exercised,is as visible as anything can be.The same would be with a grown man beginning to study mathematics;the understanding,for want of use,often sticks in very plain way,and he himself that is so puzzled,when he comes to see the connection,wonders what it was he stuck at in a case so plain.
