There is not seldom to be found,even amongst those who aim at knowledge,[those]Echo with an unwearied industry employ their whole time in books,who scarce allow themselves time to eat or sleep,but read and read and read on,but yet make no great advances in real knowledge,though there be no defect in their intellectual faculties,to which their little progress can be imputed.The mistake here is,that it is usually supposed that,by reading,the author's knowledge is transfused into the reader's understanding;and so it is,but not by bare reading,but by reading and understanding what he writ.
Thereby I mean,not barels comprehending what is affirmed or denied in each proposition (though that great readers do not always think themselves concerned precisely to do),but to see and follows the train of his reasonings,observe the strength and clearness of their connection and examine upon What they bottom.
Without this a man may read the discourses of a very rational author,writ in a language and in propositions that he very well understands,and yet acquire not one jot of his knowledge;which consisting only in the perceived,certain or probable connection of the ideas made use of in his reasonings,the reader's knowledge is no further increased than he perceives that,so much as he sees of this connection,so much he knows of the truth or probability of that author's opinions.
All that he relies on without this perception he takes upon trust upon the author's credit without any knowledge of it at all.This makes me not at all wonder to see some men so abound in citations and build so much upon authorities,it being the sole foundation on which they bottom most of their own tenets:so that in effect they have but a second hand or implicit knowledge,i.e.are in the right if such an one from whom they borrowed it were in the right in that opinion which they took from him,Which indeed is no knowledge at all.Writers of this or former arts may be good witnesses of matters of fact which they deliver,which we may do well to take upon their authority;but their credit can go no further than this;it cannot at all affect the truth and falsehood of opinions,which have another sort of trial by reason and proof,which they themselves made use of to make themselves knowing,and so must others too that will partake in their knowledge.Indeed it is an advantage that they have been at the pains to find out the proofs and lay them in that order that may show the truth or probability of their conclusions;and for this we owe them great acknowledgments for saving us the pains in searching out those proofs which they have collected for us and which possibly,after all our pains,we might not have found nor been able to set them in so good a light as that which they left them us in.
Upon this account we are mightily beholding to judicious writers of all ages for those discoveries and discourses they have left behind them for our instruction,if we know how to make a right use of them;which is not to run them over in a hasty perusal and perhaps lodge their opinions or some remarkable passages in our memories,but to enter into their reasonings,examine their proofs,and then judge of the truth or falsehood,probability or improbability of what they advance,not by any opinion we have entertained of the author,but by the evidence he produces and the conviction he affords us drawn from things themselves.Knowing is seeing,and,if it be so,it is madness to persuade ourselves that we do so be another man's eyes,let him use never so many words to tell us that what he asserts is very visible.Till we ourselves see it with our own eyes and perceive it by our own understandings,we are as much in the dark and as void of knowledge as before,let us believe any learned author as much as w e will.
Euclid and Archimedes are allowed to be knowing and to have demonstrated what they say;and yet whosoever shall read over their writings without perceiving the connection of their proofs and seeing what they knew,though he may understand all their words,yet he is not the more knowing;he may believe indeed but does not know what they say,and so is not advanced one jot in mathematical knowledge by all his reading of those approved mathematicians.
