„them. It cannot be ſaid that they « quickly forget them; for ſome chil- « dren,. at the age of only two years or « two years and a half, know a conſide- « rable part of the words of a language, « and they are more at a loſs to conceive them than retain them: now this is a proof of childhood's being the very « tealon of memory. Would it not be © more natural to ſuppoſe, that children, % at that time, imagine what they no « longer ſee, exiſts no longer, and the rather, as their joy ſhews a great mixture « of wonder, on ſeeing again the objects * which had been taken from them? al Wl © Their nurſes help them in the notion -X- © of the continuance of abfent beings, nd ii © by a play, in ſuddenly hiding one's face, and ſhewing it again. Thus they experience a hundred times in a * quarter of an hour, that what ceaſes * to appear, does not therefore ceaſe to * exiſt, Whence it follows, that to ex- E.5 © perience; » * 9 * * 4 ä — LETTER ON perience, - and experience only, we owe the notion of the continued exiſtence of objects; that it is by the touch we acquire that of their diſtance; - that the eye, perhaps, learns to ſee, as the tongue to ſpeak; that it would not be ſtrange, ſhould the aſſiſtance of one of the ſenſes be neceſſary to another, and that the touch, which aſcertains the ex- iſtence of objects without us, when preſent to our eyes, is likewiſe the ſenſe to which the confirmation, not only of their figures, and other modifications, but even of their preſence, is reſerved.” To theſe reaſonings are added, Chef: ſelden's famous experiments. The youth, whoſe cataracts were couched by that eminent ſurgeon, could not, for a long time, diſtinguiſh either dimenſions, diſtances, ſituations, or even figures. An object not above an inch ſquare, being put Prone his eye, ſo as to hide a houſe from See The Elements of Newton's Philo/aphy, by l. 8 c [ 8 ſe M.
* * F W 2 * * * N H 8 74 BLIND. #%; from him, ſeemed to him as.large as the houſe itſelf. All objects ſeemed cloſe to his eyes, as the objects of touch to the ſkin. He could not diſtinguiſh what, by means of his hands, he had judged to be round, from what he had conceived to be angular; nor diſcern with his eyes, whe- ther what he had felt to be either above or below him, was really above or be- low. He, at length, but not without great trouble, came to perceive, that his houſe was larger than his room: but how the eye gave him that idea, he could not conceive. It was not till after many repeated experiments, that he be- came aſſured of paintings repreſenting ſo- lid bodies; and when, by viewing of pictures, he was certain that what he ſaw was not bare ſurfaces, on putting his hand to a picture, he ſtood quite amazed at finding only a flat plane, without any prominence, He then aſked where the deception lay, in the ſight or the touch? Painting likewiſe had the ſame effect on ſavages. They took the figures for living BO | men, men, aſked them queſtions, and were both ſurprized and affronted at receiving no anſwer. Now this error in them cer- . tainly did not proceed from their not be- ing accuſtomed to ſee. But what can be anſwered to the other difficulties? That a man's experienced eye does, in reality, ſhew the objects better than the weak and recent organ of 2 child, or one born blind, whole cataracts have been juſt couched. Pleaſe, Ma. dam, to conſult all the proofs which the abbe de Condillac adduces at the conclu- ſion of. his Efjay on the Origin of Humat Knowledge, againſt the objections of Mr. Cheſſelden's experiments, as related by Voltaire. The effects of light on an eye, the firſt time it is affected with it, and the conditions required in the humours of that organ, the cornea, the cryſtalline, &c. are ſpecified with great perſpicuity and ex- actneſs, and leave little doubt but that vi- ſion is performed very imperfectly in 2 child opening its eyes for the firſt time, or in a blind perſon juſt couched. RE | It * — THE BLIND. 8 It muſt. therefore be granted, that we ſhould perceive an infinity of things. in objects which are unperceived by an in- fant or one born blind, though theſe ob- jects be equally painted at the bot- tom of their eyes; that for objects to ſtrike us is not enough, we mult farther attend to their impreſſions; that conſe- quently, at firſt uſing the eyes, one ſees nothing; that in the firſt inſtants of vi- fon, we feel only a multitude of con- fuſed ſenſations, to the proper diſcern- ment of which we are brought only by length of time, and habitual reflection on what paſſes in us; that it is experience alone which teaches us to compare the ſenſations with what occaſions them; that ſenſations having no eſſential reſemblance with the objects, it is from experience that we are to inform ourſelves concern- ing analogies, which ſeem to be merely politive, In a word, that the touch con- tnbutes greatly to give the eye an exact knowledge of the conformity of the ob- jets with the repreſentation it receives from = LETFTERON from it, is unqueſtionable: and I am in- clined to think, that were not every thing in nature done by laws infinitely genera]; if, for inſtance, the puncture of ſome hard bodies were painful, and that of other bodies attended with pleaſure, ye ſhould die before we had collected the hundred-millionth part of the experiment neceſſary for the preſervation of our bo- dy and our well-being.
It is, however, by no means my opi- nion, that the eye cannot inſtruct itſelf; or, if I may be allowed the expreſſion, make experiments with itſelf. For the touch to aſcertain to us the exiſtence and the figure of objects, there is no neceſſ- ty of ſeeing: and why muſt we touch, to be aſſured of the ſame things by ſight! I am no ſtranger to all the advantages of feeling, nor have I concealed them, i theſe obſervations on Saunderſon, or the dia blind man of Puiſeaux, but J cannot a- dec low it that prerogative. That the uſe dani one of the ſenſes may be improved and p.
eee by the obſervations of the other, THE BLIND Y% other, is eaſily conceived; but not that there is an eſſential dependance between their functions. There are certainly qualities in bodies that we never ſhould perceive without the touch: by the touch we be- come acquainted with the preſence of cer- tain modifications inſenſible to the eyes, or not perceiving them till informed by that ſenſe; but theſe ſervices are mutual; and in thoſe whoſe fight is more ſenſible than the touch, 1t ts the former of thoſe ſenſes which notifies to the other the ex- iſtence of objects and modifications, the he Bi minuteneſs of which would eſcape it. ad Were a piece of paper, or ſome other l ſmooth, thin, and flexible ſubſtance, put, without your knowledge, between your ht! thumb and fore- finger, it is only your of eye which could inform you that the con- tat of thoſe fingers would not be imme- diate, Let me curſorily obſerve, that to deceive a blind man in this would be in- fnitely more difficult, than impoſing upon a perſon uſed to ſee.
U 2 2 . —— — —— ——— are not a part of himſelf; that he i there is nothing more exact than the like- LETTER ON A perſon brought to his ſight would certainly be put to no ſmall trouble in acquiring a certainty that external ohjet; | ſometimes near, and ſometimes far from them; that they have forms; that ſome are larger than others; that they hare depth, &c. ſtill I make no doubt that x length he will come to ſee. them, and to ſee them ſo diſtin&ly as to. diſcern, at leal, their more obvious limits. To deny this would be ſetting aſide the deſtination of the organs; it would be forgetting the prin: cipal phænomena of viſion; it would be concealing from one's ſelf that there is no painter of ſuch {kill as to come near the beauty. and accuracy of the miniatures painted in the bottom of our eyes; that neſs of the repreſentation to the object re: preſented; that the canvas of this portrat ture is not ſo very ſmall; that there | no -confuſion. among the figures; that they take up about half an inch ſquare; and farther, that nothing is more difficult that TRE: BE FN:D: 89 than to explain how the touch would go about teaching the eye to perceive, were the uſe of this latter organ abſolutely im- poſſible without che aſſiſtance of the former.
But I, infizad of bare preſumptions, aſk, whether it is the touch which teaches the eye to diſtinguiſh colours? I do nat think the touch will be allowed ſo extra- ordinary a privilege: as granting that, the conſequence will be, that one born blind, and juſt brought to ſight, on be- ing ſhewn a black cube, with a red ſphere, be WW on a large white ground, will immediate- no diſcern the ſeveral limits of thoſe fi- the gures.
It may be anſwered, not before hs time neceſſary to a ſuitable arrangement of the humours of the eye, for the cor- nea to mould itſelf into the convexity re- quiſite for viſion; for the pupil to be ſuſ- ceptible of the dilatation and contraction proper to it; for the reticles of the retina to become of a ſenſibility adapted to the action of light; for the cryſtalline to ex- erciſe ares that 1ke- & re- tra. ere 1 that Uate; fficult that — _— — 7 Sen 4 - — — —— — — — *: — * um. * - — — 2 — — — — D — — Pr _ — — A - RS — —.
* — «+ % LETTER ON "motions; for the. muſcles to perform ſtantaneous; and by applying the reaſon complicated, as a watch, it would not bt im moving the ſpace of a ſecond. If erciſe itſelf in its forward and backward their functions well; for the optic nerves to be habituated in tranſmitting ſenſations; for the whole ball of the eye to accom: modate itſelf to all the neceſſary diſpoſi tions; and for all the parts compoſing it to concur in the execution of that miniatur which ſo much illuſtrates the demonſtn- tion, that the eye will bring itſelf to thi requiſite experience.
I own that, plain as the picture 3; which I have now repreſented to the eye of one born blind, he will not be able thoroughly to diftinguiſh its parts till the organ comes to have all the preceding conditions; that this poſſibly may be ining objected to me, to a machine a littl difficult to demonſtrate by the detail d the ſeveral motions in the drum, the fuze the wheels, the pallats, the balance, & that the hand would take up a fortnight he THE BLIND. 67 be anſwered, that theſe motions are ſimul- taneous, I reply, that poſſibly it may be the ſame with thoſe of the eye when opened for the firſt time, and of moſt of the conſecutive judgements. Whatever conditions be required in the eye to be fit for viſion, it muſt be granted, that it is not the touch which imparts them to it; that the organ acquires them of itſelf, and conſequently will come to diſtinguiſh the figures painted in it without the aſſiſtance of any other ſenſe.
eſt But it will be farther ſaid, when will it ble RY attain ſuch improvement? Perhaps much the ſooner than is thought. Do you remem- ber, Madam, the experiment of the con- cave ſpeculum, when I had the honour of attending you to the Muſeum in the king's garden, and the fright you was in at ſeeing the point of a ſword making at you with the ſame ſwiftneſs as the point uz let that which you puſhed towards the &eEſurface of the ſpeculum? and yet you night” ſufficiently accuſtomed to refer objects painted in the ſpeculums to ſomething be- 'yond = EET TER ON 3 yond them. Experience, therefore, is not 8 ſo very neceſſary, nor even ſo infallible as: imagined, for perceiving objects or their images where they are. Your very parrot affords me a proof of it. The firſt time x he ſaw himſelf in a glaſs, he ſtretched his q head towards it, and not meeting with: himſelf, whom he took for his repreſenta- tion, he went round the glaſs. Though 1 I am not for laying greater weight on the inſtance of the parrot than it will really Wl ® bear, ſtill is it an animal experiment, in Wl "* which prepoſſeſſion cannot be ſuppoſed t o OL have any ſhare. m Yet were it affirmed to EY that one born blind is not able to diſtinguiſh any WW? I thing for the ſpace of two months, | fe 3 mould not wonder at it. I ſhall only in lo 8 fer from it the neceſſity of the organs be- WI ing experienced; but not at all that the fro +8 jouch 18 neceſſary to that experience. It W*" 7 will only give me the better to ſee the Ch Propriety of letting ſuch a. perſon remain E For ſome time in the dark, when it 1s in- F AI tended he ſhould make obſervations; of giving T HE B LIND“ 35 giring his eyes a freedom of exerciſe, which will be done more conveniently in the dark than in a full light; of ſhewing him the experiments only in a kind of twilight; or, at leaſt, of procuring, in the place for making the experiments, the advantage of increaſing or diminiſhing the light at pleaſure. I ſhall only be the more inclined to agree, that theſe kind of experiments will be always very difficult, or very uncertain; and that the ſhorteſt way to rectify them, though in appearance the longeſt, is to furniſh the ſubject with ſo much philoſophy as to be able to compare the two conditions through which he has paſſed; and ro acquaint us with the dif- ference between the ſtate of a blind per- lon, and of him who has his fight. Once more, what preciſion is to be expected from one not at all accuſtomed to reflect and look into himſelf, and who, like Cheſſelden's blind man, is ſo ignorant of the advantages of fight, as to have no ſenſe of his misfortune; not conceiving mat the loſs of that ſenſe very much im- pairs pairs his gratifications? Saunderſon, who muſt be allowed to have been a philoſo- pher, certainly was not thus indifferent; and I doubt much whether he would have agreed with the author of the excellent treatiſe on ſyſtems. I am apt to think the latter of theſe philoſophers has himſelf ſlipt into a little ſyſtem in advancing, © That < had the life of man been only an uninter- << rupted ſenſation of pleaſure or of pain, “ happy without any idea of calamity, or « wretched without any idea of happi- % nels, he would have enjoy'd or ſuffer- „ ed; and that, as if ſuch had been his “ nature, he would not have looked V around to diſcover whether any being <© ſuperintended his preſervation, or ſtrove * to hurt him. So that it is the alterna- tive tranſition from one to the other of << theſe ſtates which puts him on reflect- Kc.“ Can you believe, Madam, that by a progreſſion from clear perceptions to clear "perceptions (for that is the author's method of philoſophizing, and it is the 1 | beſt) * 2 > "a "* 8. "» THE BLIND. 9g beſt) he would have ever been led to this concluſion? It is not with happineſs and miſery as with darkneſs and light; one does not- conſiſt in a total and abſolute privation of the other. Perhaps we ſhould have entertained a perſuaſion of happineſs being no leſs eſſential to us than exiſtence and thought, had we enjoyed it pure and without reſtraint; but I cannot ſay ſo much of wretchedneſs. It would have been very natural to look on it as a forced ſtate, to feel one's ſelf innocent, yet to believe one's ſelf guilty, and to ac- cuſe or excuſe nature as at preſent. 2 Does the abbe think that a child in in- tenſe pain cries only from his pain not having been without intermiſſion ſince his birth? If he anſwers me, That to exiſt and ſuffer would be the ſame thing to one „who had always ſuffered; and that his pain allowed of intermiſſion without * deſtroying his exiſtence; would never “have come into his thoughts:” I re- ply, The man living in continual miſery poſſibly might not have faid, What have I 5 EY * i 4 i OM - 96 LETTER ON J done, that I ſhould ſuffer thus? But why might he not have ſaid, What - have I done, that I ſhould be brought into being? Yet I fee not why he might not have made uſe of the two verbs, I exiſt and I ſuffer, as ſynonymous, one for proſe and the other for poetry, like I live and 1 kreathe. You will, moreover, Madam, obſerve better than I, that this paſſage of the abbẽ's book is ſo admirably beautiful, and I am very much afraid, that on com- paring my criticiſm with his reflection, you will ſay: You like Montaigne in the - wrong better than Charon in the right.
What, ever digreſſing! you cry out. Yes, Madam, our treaty allows it. Now my opinion on the two foregoing queſtions rs this: the firſt time the eyes of one born blind open to the light, he will have no perception of any thing; his eye will re- quire ſome time for experience, but that it will acquire of itſelf, and without any help from the touch; and it will come not only to diſtinguiſh colours, but diſ- cern, at leaſt, the groſſer limits of ob- "2 | jects.
THE BELEIND. 97 Jets. Let us now ſee whether, ſuppo- ſing he acquired this aptitude in a very ſhort time, or arrived at it by moving his eyes in the dark apartment to which he had been prudently confined, and deſired to uſe that exerciſe for ſome time after the operation, as preparatively to the experiments; let us, I ſay, fee. whether his fight would indicate to him the bodies which he had touched, fo as to give them their proper amd? "This is the final queſtion.
e That my manner of performing it may ; pleaſe you, as you love method, I will di- £ ſtinguiſh ſeveral ſorts of perſons on whom - the experiments may be tried. If they are 1 dullards, without education, void of no knowledge, and unprepared, I hold, that 5 on the organ being rectified by the ca- 5 taract operation, and the eye healed, the portraiture of objects in it will be very diſtin&t; but ſuch perſons not being uſed to any kind of reaſoning, and not know- ing any thing of ſenſation or idea, and unable to compare the repreſentations F received 8 LETTER ON received by feeling, with thoſe which the eye conveys to them, will at once ſay, that is round, that is ſquare, ſo that their judgement is not to be reſted on; or even they will frankly own that they do not perceive any thing in the objects before their eyes, like what they have handled. Others there are, who comparing the apparent figures of bodies with the im- .prefſed ones made on their hands, will, by an ideal application of their feeling to thoſe bodies before them, ſay of one, that it is a ſquare, and of another, that it is a circle, without well Knowing why, their compariſon of the ideas which they have received from the touch, with thoſe given them by the light, not being clear and diſtinct enough to convince their judgement. | I ſhall now, Madam, without any di- greſſion, ſuppoſe the experiment made on a Metaphyſician. He, I make no . doubt, would, from the very firſt inſtant of his perceiving objects diſtinctly, rea- ſon as if he had ſeen them all his life; and — 9 E HE. BL IND: 997 -2 — and after comparing the idea received from his fight, with thoſe he had im- bibed from feeling, he would declare, as poſitively as you or I, „I am very « much inclined to think this the body « which I have always called a circle, « and that again what I named a ſquare, but will not aſſert it to be really ſo. Who « has revealed to me, that if I laid my « hands on them, they would not va- „ niſh? How do I know whether the “ objects of my ſight are intended to „% be likewiſe objects of my feeling? I „know not whether what is viſible be « palpable; but were I not under this , “ uncertainty, and did I firmly believe t % on the word of thoſe about me, that - «* what I fee is really what I touched, *« I ſhould be little the better. They * may change in my hands, and thus < the” ideas. by feeling be quite oppo- 0 * ſite to thoſe reſulting from ſight. nt „Gentlemen, would he add, „ this a- body appears to me the ſquare," this e; the circle; but that they are to the 1 feeling 100 LETTER ON < 3 as to the ſight, is what 1 have no knowledge of.“ If to the Metaphyſician we ſubſtitute a Geometrician, as Saunderſon to Locke, he will, like him, ſay, “That if his eyes e may. be relied on, of the two figures e before him, this is what he called a 0 ſquare, and this a circle; for I per- < ceive,“ would he add, that it is only <« in the firſt I can diſpoſe the threads and place the large headed pins which «denoted the angular points of the <« ſquare; and it is only the round which * adrhits of the arrangement of my threads, uſed in demonſtrating the pro- «© perties of my circle: ſo, therefore, ce that is a circle, and that is a ſquare; * but would he with Locke have proceed- « ed? On my beginning to feel theſe * figures, they may perhaps transform © themſelves into each other, fo that „ the ſame figure would ſerve me << in demonſtrating to the blind the pro- % perties of a Circle, and to thoſe who “ have their ehr the properties of a ©: - < ſquare.
THE BLIN D. 102 0 ſquare. I might poſſibly ſee a ſquare, « and at the ſame time feel a circle. « They, to whom I demonſtrated the « properties of a circle and of a ſquare, « had not their hands on my Abacus, „ nor did they touch the threads which I had ſtretched along as the limits of « my figures, yet.did they comprehend me; they therefore did not ſee a ſquare, „ when I felt a circle, otherwiſe we ſhould © never have underſtood one another: I „ ſhould have been delineating one figure; « and demonſtrating the properties of « another; I ſhould have given them a « ſtraight line for the arch of a circle, and „an arch of a circle for a ftraight line; but as they all underſtand me, « all men then ſee alike; therefore, « what they ſaw ſquare, I ſaw ſuch, and circular what they faw circular; % ſo, that is what I have always named « a ſquare, and that is what I have al- « ways named a circle.” I have inſtead of a fphere put a z circle, and a ſquare inſtead of a cube; becauſe: ' = 0. in = TETIERDON in all appearance, it is only by experi- ment that we come to judge of diftances, and of | courſe, | he who uſes his eyes for the firſt time, ſees only ſurfaces, with- out knowing any thing of projecture; the projecture of a body to the fight, conſiſting in ſome of its points, appear- ing more to us than the other. | But could a perſon born blind determine concerning the projecture and ſolidity of bodies, at the firſt view of his eyes, and be able to diſtinguiſh not only the circle from the ſquare, but like- wiſe the ſphere from the cube; yet do I not therefore think that this will hold good with regard to more compli- cated objects. M. de Reaumur's girl, who had been born blind, did very pro- bably diſtinguiſh colours; but it is great odds that her judgement of the ſphere and the cube was purely gueſs-work; and I am firmly perſuaded, that without a revelation, it was not poſſible for her to know her gloves, her bed-gown, and ſhoes. | The modifications are ſo multifarious, 6 bd iii ＋ H E B LIND. 107 rious, and the total form of them h little agreeing with that of the parts which they cover, that Saunderſon would have been infinitely more puzzled to find out the uſe of his ſquare, than M. d' Alem- bert, or M. Clairaut, in n the uſe of his tables. ä Saunderſon would infallibiy have ſup- poſed a geometrical relation between things, and the uſe of them; and in conſequence have perceived in two or three analogies, that his cap was made for his head. But what would he have thought of the angles and tuft of his trencher cap? What can this tuft be for? Why four angles rather than ſix? And thoſe two modifications, which to me are matters of ornament, would to him have been the ſource of a multitude of ab- ſurd reaſonings, or rather an occaſion of excellent ſatyr e on what we term good taſte. | Things duly - conſidered, it will bs owned, that the difference between a perfon. who has always ſeen, but to whom F4 the cas FWETTER ON the uſe of an object is unknown, and one who knows the uſe of an object, but who has never ſeen, is not on the ſide of the latter; yet, do you think, Madam, that were a head-dreſs to be ſhewn you to-day for the firſt time, you would ever gueſs it to be a part of dreſs, and par- ticularly intended for the head? But if it de the more difficult for one born blind, and feeing for the firſt time, to judge rightly of objects, the more forms and modifications they have, why might he. not take a ſpectator quite dreſſed, and fitting motionleſs: in an elbow chair, for a piece of furniture, or a machine; maken by the wind, for a fſelf-moving, animated, and thinking being? How many things our ſenſes ſuggeſt to vs, Madam; and were it not for our eyes, how apt ſhould we be to ſuppoſe that a block of marble thinks and feels!
It remains then to be proved, that Saunderſon would have been certain of * not being miſtaken in the judge- ment * and a tree with its boughs and leaves . T H E BLIND. 105 ment he had juſt given only of the circle and the ſquare; and that there are caſes, . when the reaſoning and experience of others may aſſiſt ſight, concerning the relation of the touch, and convince it, that what a thing is to the eye, it is likewiſe ſo to the touch. 2086 It would, however, be not the leſs eſſential in the demonſtration of ſome propoſitions of eternal Truth, as they are termed, to try one's demonſtration by depriving it of the teſtimony of the ſenſes; for you are very well aware, Madam, that would any one go about proving to you, that the projection of two parallel lines on a2 plane is to be made by two conver- gent lines, becauſe two rows of trees ap- pear ſuch, it would be forgetting that the propoſition. is as true for one that is blind, as for himſelf. | But the preceding ſuppoſition. of one born blind fuggeſts two others: one of a man, who has. had his ſight from his birth, but without ever having the ſenſe of 2 and the other of a man in 65. whom mo LTETHAER ON -whom the ſight and touch were in perpe- tual contradiction. The former might be *aſked; whether if the ſenſe: he wants were given to him, and his ſight be precluded by a fillet over his eyes, he ſhould know bodies by the feeling? It is evident that geometry, provided he was ac. -quamted with it, would furniſh him with an infallible way for being certain whe- ther the teſtimonies of the two ſenſes be contradictory or not. It would be only taking the cube or the ſphere into ki hands, demonſtrate its properties, and, if underſtood, pronounce, that what he feels to be a cube, is ſeen to be a cube, and that conſequently what he holds is a cube. As to one who is a ſtranger to that ſcience, I believe that he would not more eaſily diſcern the cube from the ſphere by touch, than M. Molineux's blind man en them by the ſight.
As to him in whom the ſenſations of ſight Sad of feeling are in a perpetual contradic- tion, I know not what he would think of Forms, order, e beauty, defor- * THE BLIND. 10 ity, &c. He would, in all likelihood, be, with regard to thoſe things, as we are with regard to the extenſion and real duration of beings. He would, in gene- ral, determine that a body has a form; but he.muſt be inclined to think that it is neither that which he fees, nor that which he feels. Such a one might be diſ- pleaſed with his ſenſes, but the ſenſes would be neither pleaſed nor diſpleaſed with the objects. Were he diſpoſed to charge one of them with deception, I fancy it would fall on the touch. A hundred circumſtances would biaſs him to think that the figure of objects changes rather by the action of his hands on tnem, than by that of the objects on his eyes. But in conſequence of theſe prejudices, the difference of hardneſs and ſoftneſs, which he would find in bodies, would put him to no ſmall perplexity. But from our ſenſes not being in con- tradiction concerning gſigures, does it therefore follow that they are better known to us? Who has told us that we 8 have i 18 LETTER oN have not to do with falſe witneſſes? yet we pronounce ſentence. Alas! Madam, when human knowledge comes to be put in Montaigne's ſcale, we are ready to adopt his motto, For what do we „ know? What matter is? No. What “ ſpirit and thought is? Still leſs. What “ motion, ſpace, and duration are? Not in the leaſt. What geometrical truths are? « Aſk any honeſt mathematicians, and they <* will own to you, that their propoſitions * are all identical, and that fo many vo- lumes, for inſtance, on the circle, amount to no more than repeating to us, in a * hundred thouſand different ways, that it « is a figure in which all the lines drawn from the center to the circumference are * equal.*” Thus we fcarce know any thing: | 758 3 blind man, moviog in the ſphere of a mathe- - matician, ſeems a phænomenon difficult to be ac- counted for: Tully mentions it as a thing ſcarce credible in his own qggſter in philoſophy, Diodorus, That he exerciſed himſelf in philoſophy with more ky” aſſiduity after he became blind; and what he 3 t next to impoſſible, to be done without «6 * gu „ TH E B L I'N D. 109 yet, what numbers of writings! the au- thors of which have all pretended to knowledge. I cannot account for the world's not being tired of reading, and Jearning nothing, « ſight, that he profeſſed geometry, deſeribing his « diagrams ſo expreſly, that his ſcholars drew every line in its proper directions.“ | St. Jerom relates a more remarkable. circumſtance in. Didymus of Alexandria, who, though blind « from his infancy, and therefore ignorant of the « yery letters, not only learnt logie, but geometry « alſo to perfection, which ſeems the moſt of any « thing to require the help of ſight.”
Trithemius, de Scriptoribus:Eecleſ. -mentions Nicaiſe de Voerde, at Mechlen, who, though « blind from the firſt year of his age, became fo « eminent in learning, that he taught the canon and « civil law in the univerſity of Cologne, and quoted books only from having heard them read to him.“ I have further heard of a Hollander, and ſome others, whom blindneſs did not hinder from excelling in mathematical learning. Indeed, if we confider that the ideas of extended quantity, which are.the chief objects of mathematics, may as well be acquired from the ſenſes of feeling, as that of fight; that a rm and ſteady attention is the principal qualifica- ton for this ſtudy; and that the blind are necefiarily | more To LETTER, Ke.
nothing, unleſs it be for the very fame rex ſons as T have been talking to you for thek two hours, without being tired, and with. out ſaying any thing to you. I am, with ry" reſpect, Madam, Tour moſt humble, And moſt obedient Servant, * * * + more abſtracted than others; we ſhall perhaps find reaſon to think there is no other branch of ſcience more adapted to their circumſtances. N of Saur. derſon, prefixed to his Algebra. | Profeffor Saunderſon could ſpell very well; he knew the ſhapes of the letters, both ſmall and capi- tal, and would ſometimes amuſe himſelf, when op- Portunity offered, with reading inſcriptions on tombe ſtones with his fingers. He frequently regretted hi not applying himſelf to learn to write in his younger years, which he made no queſtion he could hare _ nene unn Didionary REMARK REMARKABLE.
EC A ON: E 8 "OF BLINDNESS.
An account of obſervations made Wt, young gentleman who was born blind, or loſt his fight ſo early that be bad no uM remembrance of ever having ſeen, and was couched when between thirteen and avi Wl fourteen years of ge. From Mr.
op- age 1 E 5 mb- — | bi HOUGH we ſay of this gentleman 1 that he was blind, as we do of all ave people that have ripe cataracts, yet they are never ſo blind from that cauſe but K. they can diſcern day from night, and, for = | the LM „