Secondly,he must do that which he will find himself very averse to,as judging the thing unnecessary or himself incapable of doing it.He must try whether his principles be certainly true or not,and how far he may safely rely upon them.This,whether fewer have the heart or the skill to do,Ishall not determine;but this I am sure,this is that which everyone ought to do who professes to love truth and would not impose upon himself which is a surer way to be made a fool of than by being exposed to the sophistry of others.The disposition to put any cheat upon ourselves works constantly and we are pleased with it,but are impatient of being bantered or misled by others.
The inability I here speak of is not any natural defect that makes men incapable of examining their own principles.To such,rules of conducting their understandings are useless,and that is the case of very few.The great number is of those whom the ill habit of never exerting their thoughts has disabled;the powers of their minds are starved by disuse and have lost that reach and strength which nature fitted them to receive from exercise.
Those who are in a condition to learn the first rules of plain arithmetic and could be brought to cast up an ordinary sum are capable of this,if they had but accustomed their minds to reasoning;but they that have wholly neglected the exercise of their understandings in this way will be very far at first from being able to do it and as unfit for it as one unpracticed in figures to cast up a shop-book,and perhaps think it as strange to be set about it.And yet it must nevertheless be confessed to be a wrong use of our understandings to build our tenets (in things where we are concerned to hold the truth)upon principles that may lead us into error.We take our principles at haphazard upon trust and without ever having examined them,and then believe a whole system upon a presumption that they are true and solid.And what is all this but childish,shameful,senseless credulity?
In these two things,viz.,an equal indifference for all truth (I mean the receiving it in the love of it as truth,but not loving it for any other reason before we know it to be true)and in the examination of our principles and not receiving any for such nor building on them till we are fully convinced,as rational creatures,of their solidity,truth and certainty,consists that ******* of the understanding which is necessary to a rational creature and without which it is not truly an understanding.It is conceit,fancy,extravagance,anything rather than understanding,if it must be under the constraint of receiving and holding opinions by the authority of anything but their own,not fancied but perceived,evidence.
This was rightly called imposition,and is of all other the worst and most dangerous sort of it.For we impose upon ourselves,which is the strongest imposition of all others,and we impose upon ourselves in that part which ought with the greatest care to be kept free from all imposition.The world is apt to cast great blame on those who have an indifferency for opinions,especially in religion.I fear this is the foundation of great error and worse consequences.To be indifferent which of two opinions is true is the right temper of the mind that preserves it from being imposed on and disposes it to examine with that indifference till it has done its best to find the truth;and this is the only direct and safe way to it.But to be indifferent whether we embrace falsehood for truth or no is the great road to error.Those who are not indifferent which opinion is true are guilty of this;they suppose,without examining,that what they hold is true and then think they ought to be zealous for it.
Those,it is plain by their warmth and eagerness,are not indifferent for their own opinions,but methinks are very indifferent whether they be true or false,since they cannot endure to have any doubts raised or objections made against them;and it is visible they never have made any themselves,and so,never having examined them,know not nor are concerned,as they should be,to know whether they be true or false.
These are the common and most general miscarriages which I think men should avoid or rectify in a right conduct of their understandings,and should be particularly taken care of in education.The business whereof in respect of knowledge is not,as I think,to perfect a learner in all or any one of the sciences,but to give his mind that *******,that disposition and those habits that may enable him to attain any part of knowledge he shall apply himself to or stand in need of in the future course of his life.This and this only is well principling,and not the instilling a reverence and veneration for certain dogmas under the specious title of principles,which are often so remote from that truth and evidence which belongs to principles,that they ought to be rejected as false and erroneous;and is often the cause to men so educated,when they come abroad into the world and find they cannot maintain the principles so taken up and rested in,to cast off all principles and turn perfect skeptics,regardless of knowledge and virtue.
There are several weaknesses and defects in the understanding,either from the natural temper of the mind or ill habits taken up,which hinder it in its progress to knowledge.Of these there are as many possibly to be found,if the mind were thoroughly studied,as there are diseases of the body,each whereof clogs and disables the understanding to some degree and therefore deserves to be looked after and cured.I shall set down some few to excite men,especially those who make knowledge their business,to look into themselves and observe whether they do not indulge some weakness,allow some miscarriages in the management of their intellectual faculty,which is prejudicial to them in the search for truth.