The definition of a fpecies, is nothing but the definition of the genus, with the addition of a fpecific difference; and the divifion of things into fpecies is the work of the mind, as well as their divifion into genera and claflfes. A fpecies, a genus, an order, a clafs, is only a combination of attributes miade by the mind, and called by one name. There is therefore the fame reafon for giving the name of idea to every attribute, and to every fpecies and genus, whether higher or lower: Thefe are only more complex attributes, or combinations of the more SENTIMENTS concermvg JUDGME NT. 223 more fimple. And though it might be impro-^ HAP, per, without neceflity, to multiply beings, ^ ' which they believed to have a real exiftence; yet, had they feen that ideas are not things that exift, but things that are conceived, they would have apprehended no danger nor expence from their number.
Simple attributes, fpecies and genera, lower or higher, are all things conceived without re- gard to exiftence; they are univerfals; they are expreffed by general words; and have an equal title to be called by the name of ideas.
I hkewife agree with thofe ancient Philofo- phers, that ideas are the obje6t, and the fole obje£t of fcience, ftri£lly fo called; that is, of demonftrative reafoning.
And as ideas are immutable, fo their agree- ments and difagreements, and all their relations and attributes, are immutable. All mathema- tical truths are immutably true. Like the ideas about which they are converfant, they have no relation to time or place, no depen- dence upon exiftence or change. That the angles of a plane triangle are equal to two right angles, always was and always will be true, though no triangle had ever exifted.
The fame may be faid of all abftradl truths. On that account they have often been called eternal truths: And for the fame reafon the Pythagoreans afcribed eternity to the ideas about which they are converfant. They may very properly be called neceflary truths; be- caufe it is impoflible they (hould not be true at all times and in all places.
Such is the nature of all truth that can be difcovered, by perceiving the agreements and difagreements of ideas, when we take that word in its primitive fenfe. And that Mr. Locke, in ESSAY vi.
C H A P. In his definition of knowledge, had chiefly in ^ think from the examples he gives to illuftrate it.
But there is another great clafs of truths, which are not abftraft and neceflary, and there- fore cannot be perceived in the agreements and difagreements of ideas. Thefe are all the truths we know concerning the real exiflence 6f things; the ruth of our own exiflence; of tlic exigence of other things, inanimate, animal and rational, and of their various attri- butes and relations.
Thefe truths may be called contingent truths. I except only the exiflence and attri- butes of the Supreme Being, which is the only neceffary truth I know regarding exiflence.
All other beings that exift, depend for their exiflence, and all that belongs to it, upon the will and power of the firfl caufe; therefore, neither their exiflence, nor their nature, nor any thing that befals them, is necelTary, but contingent.
But although the exiflence of the Deity be neceffary, I apprehend w'e can only deduce it from contingent truths. The only arguments for the exiflence of a Deity which I am able to comprehend, are grounded upon the know- ledge of my own exiflence, and the exiflence of other finite beings. But thefe are contin- gent truths.
I believe, therefore, that by perceiving agreements and difagreements of ideas, no con- tingent truth whatfoever can be known, nor the real exiflence of any thing, not even our own exiflence, nor the exiflence of a Dqity, which is a neceifary truth. Thus I have en- deavoured SENTIMENTS concerning JUDGMENT. 225 deavoured to fhew what knowledge may, and CHAP, what cannot be attained, by perceiving the ^^^• agreements and difagi eements of ideas, when ^"""^^"'^ •we take that word in its primitive fenfe.
We are, in the next place, to confider, whe- ther knowledge confifts in perceiving the agree- ment or difagreement of ideas, takin<^ ideas in any of the fenfes in which the word is ufed by Mr. Locke and other modern Philofophers.
1. Very often the word idea is ufed fo, that to have the idea of any thing is?iperiphrafis for conceiving it. In this fenfe, an idea is not an objed of thought, it is thought itfclf. It is the a6t of the mind by which we conceive any ob- ject. And it is evident that this could not be the meaning which Mr. Locke had in view in his definition of knowledge.
2. A fecond meaning of the word idea is that which Mr. Locke gives in the introduc- tion to his Eifay, when he is making an apolo- gy for the frequent ufe of it. *' It being that " term, I think, which ferves bed to (land for " whatfoever is the obje6t of the underftand- *' ing when a man thinks, or whatever it is *' which a man can be employed about in " thinking.'* By this definition, indeed, every thing that can be the objeft of thought is an idea. The objects of our thoughts may, I think, be redu- ced to two clalfes.
The firft clals comprehends all thofe obje£ts which we not only can think of, but which we believe to have a real exiflence. Such as the Creator of all things, and all his creatures that fall within our notice. I can think of the fun and moon, the earth and fea, and of the vari- ous animal, vegetable, and inanimate produc- VoL. II. Q^ tions diS ESSAY VI, C H A P.tions with which it hath pleafed the bountiful ^^^- Creator to enrich our globe. I can think of myfelf, of my friends and acquaintance. I think of the author of the Effay with high efteem. Thefe, and fuch as thefe, are objefts of the underftanding which we believe to have real exigence.
A fecond clafs of objects of the underftand- ing which a man may be employed about in thinking, are things which we either believe never to have exifted, or Vvhich we think of without regard to their exiftence.
Thus, I can think of Don Quixote, of the ifland of Laputa, of Oceana, and of Utopia, which I believe never to have exifted. Every attribute, every fpecies, and every ge- nus of things, confidered abftradly, without any regard to their exiftence or non-exiftence, may be an objeft of the underftanding.
To this fecond clafs of objeds of the under- ftanding, the name of idea does very properly belong, according to the primitive fenfe of the word, and I have already confidered what knowledge does, and what does not confift in perceiving the agreements and difagreements of fuch ideas.
But if we take the word idea in fo extenfive a fenfe as to comprehend, not only the fecond, but alfo the firft clafs of objecls of the under- ftanding, it will undoubtedly be true, that all knowledge confifts in perceiving the agree- ments and difagreements of ideas: For it is impoflible that there can be any knowledge, any judgment, any opinion, true or falfe, which is not employed about the objecls of the underftanding. But whatfoever is an objea SENTIMENTS concerning JUDGMENT. 227 je6t of the underftanding is an idea, according ^ ^j^ P* to this fecond meaning of the word. o-^r— » Yet I am perfuaded that Mr. Locke, in his definition of knowledge, did not mean that the word idea fhould extend to all thofe things which we commonly confider as objects of the underftanding.
Though Bifhop Berkeley believed that fun, moon, and ftars, and all material things, are ideas, and nothing but ideas, Mr. Locke no where profeifes this opinion. He believed that we have ideas of bodies, but not that bodies are ideas. In like manner, he believed that we have ideas of minds, but not that minds are ideas. When he enquired fo care- fully into the origin of all our ideas, he did not furely mean to find the origin of whatfo- ever may be the objeft of the underftanding, nor to refolve the origin of every thing that may be an object of underftanding into fenfa- tion and refledion.
3. Setting afide, therefore, the two mean- ings of the word idea before mentioned, as meanings which Mr. Locke could not have in his view in the definition he gives of know- ledge, the only meaning that could be intend- (6d in this place is that which I before called the Philofophical meaning of the word idea, tvhich hath a reference to the theory commonly received about the manner in which the mind perceives external objects, and in which it re- members and conceives objefts that are not prefent to it. It is a very ancient opinion, and has been very generally received among Philofopers, that we cannot perceive or think of fuch obje(^s immediately, but by the medi- CHAP, um of certain images or reprefentatives of ^^^- them really exiting in the mind at the time. "'''■"'' To thofe images the ancients gave the name of fpecies and phantafms. Modern Philofo- phers have given them the name of ideas. " 'Tis evident," fays Mr. Locke, book 4. ch. 4. " the mind knows not things immedi- " ately, but only by the intervention of the " ideas it has of them." And in the fame pa- ragraph he puts this queflion: " How fhall the " mind, when it perceives nothing but its " own ideas, know that they agree with " things themfelves?"
This theory I have already confidered, in treating of perception, of memory, and of conception. The reader will there find the reafons that lead me to think, that it has no folid foundation in reafon, or in attentive re- flection upon thofe operations of our minds; that it contradids the immediate diftates of our natural faculties, which are of higher au- thority than any theory; that it has taken its rife from the fame prejudices which led all the ancient Philofophers to think that the Deity could not make this world without fome eter- nal matter to work upon, and which led the Pythagoreans and Platonifts to think, that he could not conceive the plan of the world he was to make without eternal ideas really exift- ing as patterns to work by; and that this theo- ry, when its neceflary confequences are fairly purfued, leads to abfolute fcepticifm, though thofe confequences were not feen by moft of the Philofophers who have adopted it.
I have no intention to repeat what has be- fore been faid upon thofe points; but only, taking ideas in this fenfe, to make fome obfervations SENTIMENTS concerning JUDGMENT. 229 vations upon the definition which Mr. Locke CHAP. gives of knowledge.
Firjl, If all knowledge confills in perceiving the agreements and difagreements of ideas, that is, of reprefentative images of things ex- ifling in the mind, it obvioufly follows, that if there be no fuch ideas, there can be no knowledge: So that, if there fliould be found good reafon for giving up this philofophical hypothefis, all knowledge mufl go along with it.
I hope, however, it is not fo; and that though this hypothefis, like many others, Ihould totter and fall to the ground, knowledge will continue to ftand firm, upon a more per- manent bafis.
The cycles and epicycles of the ancient Af- tronomers were for a thoufand years thought abfolutely neceflary to explain the motions of the heavenly bodies. Yet now, when all men believe them to have been mere fiftions, aftro- nomy has not fallen with them, but (lands up- on a more rational foundation than before. Ideas, or images of things exifting in the mind, have for a longer time been thought neceflary for explaining the operations of the underftanding. If they Ihould likevvife at lafl be found to be fictions, human knowledge and judgment would fuft'er nothing, by being difengaged from an unwieldly hypothefis. Mr. Locke furely did not look upon the exiftence of ideas as a philofophical hypothefis. He thought that we are coiifcious of their exif- tence, otherwife he would not have made the exiftence of all our knowledge to depend upon the exiftence of ideas.
Secondlyt Secondlyt CHAP. Secondly, Suppofing this hypyothefis to be vJy-^ true, I agree \yith Mr. Locke, that it is an ~^ " evident and necellary confequence that our knowledge can be converfant about ideas only, and mull confift in perceiving their attributes and relations. For nothing can be more evi- dent than this, that all knowledge, and all judgment and opinion, muft be about things which are or may be immediate objects of our thought. What cannot be the obje£t of thought, or the object of the mind in think- ing, cannot be the obje<Et of knowledge or of opinion.
Every thing we can know of any objeft muft be either fome attribute of the object, or fome relation it bears to fome other object or objefts. By the agreements and difagreements of ob- je6ts, I apprehend Mr. Locke intended to ex- prefs both their attributes and their relations. If ideas then be the only objects of thought, the confequence is neceifary, that they muft be the only objefts of knowledge, and all know- ledge muft confift in perceiving their agree- ments and difagreements, that is, their attri- butes and relations.
The ufe I would make of this confequence, is to fhow that the hypothecs muft be falfe, from which it neceffarily follows: For if we have any knowledge of things that are not ideas, it will follow no lefs evidently, that ideas are not the only objects of our thoughts.
Mr. Locke has pointed out the extent and limits of human knowledge in his fourth book, with more accuracy and judgment than any Philofopher had done before; but he has not confined it to the agreements and difagree- ments of ideas. And I cannot help thinking, that SENTIMENTS concfrnln^ JUDGMENT. 231 that a great part of that book is an evident re-C H A P. futation of the principles laid down in the be- ^^^' ginning of it.
Mr. Locke did not believe that he himfeli was an idea; that his friends and acquaintance were ideas j that the Supreme Being, to fpeak with reverence, is an idea; or that the fun and moon, the earth and the fea, and other exter- nal objeds of fenfej are ideas. He believed that he had foine certain knovi^lcdge of all thofe objects. His knowledge, therefore, did not confift folely in perceiving the agreements and difagrcements of his ideas: For, furely, to perceive the exiftence, the attributes, and re- lations of things, which are not ideas, is not to perceive the agreements and difagreements ot ideas. And if things which are not ideas be objects of knowledge, they muft be obje<3:s of thought. On the contrary, if ideas be the only objects of thought, there can be no know- ledge either of oUr dwn exiftence, or of the exiftence of external objeds, or of the exif- tence of a Deity.
This confequence, as far as concerns the exiftence of external objects of fenfe, was af- terwards deduced from the theory of ideas by Biftiop Berkeley with the cleareft evidence; and that author chdfe rather to adopt the con- fequence than to reje£t the theory on which it was grounded. But, with regard to the ex- iftence of our own minds, of other minds, and of a Supreme Mind, the Bifhop, that he might avoid the confequence, rejected a part of the theory, and maintained, that we can think of of minds, of their attributes and relations, without ideas, Mr.
23t ESSAY VL Mr. Hume faw very clearly the confequen- ces of this theory, and adopted them in his fpeculative moments; but candidly acknow- ledges, that, in the common bufmefs of life, he found himfelf under a neceffity of believing with the vulgar. His Treatife of Human Na- ture is the only fyflem to which the theory of ideas leads; and, in my apprehenfion, is, in all its parts, the neceffary confequence of that theory.
Mr. Locke, however, did not fee all the confequences of that theory; he adopted it without doubt or examination, carried along by the ftream of Philofophers that went before him; and his judgment and good fenfe have led him to fay many things, and to believe many things that cannot be reconciled to it.
He not only believed his own exiftence, the exiflence of external things, and the exiftence of a Deitv; but he has fhown very juflly how we come by the knowledge of thefe exiflen- ces.
It might here be expected, that he fhould have pointed out the agreements and difagree- mcnts of ideas from which thefe exillences are deduced; but this is impoffible, and he has not even attempted it.
Our own exiftence, he obferves, ive know intuitively; but this intuition is not a percep- tion of the agreement or difagreement of ideas; for the fubjedt of thepropofition, lex'iji, is not an idea, but a perfon.
The knowledge of external objects of fenfe, he obferves, -we can have only by fenfation. This fenfation he afterwards exprefles more clearly by the tejlimony of our fenjes, which are the proper and fole judges of this tl/mg; whofe teftimony SENTIMENTS concerning JUDGMENT. 233 tcftimony is the greateji ajfurance we can po/Jtbly^ HAP. have, and to which our faculties can attain. ' This is perfedly agreeable to the common fenfe of mankind, and is perfedly underftood Jby thofe who never heard of the theory ot ideas. Our fenfes teflify immediately the ex- iftence, and many of the attributes and relati- ons of external material beings; and, by our conftitution, we rely with aflurance upon their teftimony, without feeking a reafon for doing io. This aflurance, Mr. Locke acknowledg- es, deferves the name of knowledge. But thofe external things are not ideas, nor are their at- tributes and relations the agreements and dif- agreements of ideas, but the agreements and difagreements of things which are not ideas.
To reconcile this to the theory of ideas, Mr, Locke fays. That it is the adual receiving of ideas from without that gives us notice of the exi/ience of thofe external things.
This, if underftood literally, would lead us back to the dodlrine of Aristotle, that our ideas or fpecies come from without from the external objects, and are the image or form of thofe objedts. But Mr. Locke, I believe, meant no more by it, but that our ideas of fenfe muft have a caufe, and that we are not the caufe of them ourfelves.
Bifhop Berkeley acknowledges all this, and fhews very clearly, that it does not afford the lead fliadow of reafon for the belief of any material objedt. Nay, that there can be no- thing external that has any refemblance to our ideas but the ideas of other minds.
It is evident, therefore, that the agree- ments and difagreements of ideas can give us no knowledge of the exiflence of any material thing.
P-thing. If any knowledge can be attained of things which are not ideas, that knowledge is a perception of agreements and difagreements, not of ideas, but of things that are not ideas.
As to the exiftence of a Deity, though Mr. Locke was aware that Des Cartes, and ma- ny after him, had attempted to prove it merely from the agreements and difagreements of ideas; yet " he thought it an ill way of efta- " bHfhing that truth, and filencing Atheifts, *' to lay the whole ftrefs of fo important a " point upon that fole foundation.'* And therefore he proves this point with great ftrength and folidity, from our exiftence, and the exiftence of the fenfible parts of the uni- verfe. By memory, Mr. Locke fays, we have the knowledge of the paft exiftence of feveral things: But all conception of paft exiftence, as well as of external exiftence, is irreconcilea- ble to the theory of ideas; becaufe it fuppofes that there may be immediate objefts of thought, ■which are not ideas prefently exifting in the mind.
I conclude therefore, that if we have any knowledge of our own exiftence, or of the exif- tence of what we fee about us, or of the ex- iftence of a Supreme Being; or if we have any knov/ledge of things paft by memory, that knowledge cannot confift in perceiving the agreements and difagreements of ideas.
This conclufion, indeed, is evident of itfelf: For if knowledge conftfts folely in the percep- tion of the agreement or difagreemeiit of ideas, there can be no knowledge of any propofition which does not exprefs fome agreement or dif- agreement of ideas; confequently there can be no knowledge of any propofition, which exprelles either the exiftence, or the attributes or SENTIMENTS concerning JUDGMENT. ^^S' CHAP or relations of things, which are not ideas. ^^^ If therefore the theory of ideas be true, there w.-v-*j can be no knowledge of any thing but of ideas. And, on the other hand, if we have any know- ledge of any thing befides ideas, that theory mufl be falfe.
There can be no knowledge, no judgment, or opinion about things which are not imme- diate objects of thought. This I take to be felf-evident. If, therefore, ideas be the only immediate objects of thought, they mud be the only things in nature of which we can have any knowledge, and about which we can have any judgment or opinion.
This neceflary confequence of the^common doftrine of ideas Mr. Hume faw, and has made evident in his Treatife of Human Na- ture; but the ufe he made of it was not to overturn the theory with which it is neceflarily connected, but to overturn all knowledge, and to leave no ground to believe any thing whatfoever. If Mr. Locke had feen this con- fequence, there is reafon to think that he would have made another ufe of it.
That a man of Mr. Locke's judgment and penetration did not perceive a confequence fo evident, feems indeed very ftrange; and I know no other account that can be given of it but this, that the ambiguity of the word idea has milled him in this, as in feveral other in- ftances. Having at firfl: defined ideas to be whatfoever is the objedt of the underft anding when we think, he takes it very often in that unlimited fenfc; and fo every thing that can be an object of thought is an idea. At other times, he ufes the word to fignify certain re- prefentative images of things in ths mind, which ^^TT^ ^ which Philofophers have fuppofed to be imme- ^^,.._^^ diate objefts of thought. At other times, things conceived abftradly, v/ithout regard to their exiflence, are called ideas. Philofophy is much indebted to Mr. Locke for his obfer- vations on the abufe of words. It is pity he did not apply thefe obfervations to the word idea, the ambiguity and abufe of which has very much hurt his excellent Efiay.
There are fome other opinions of Philofo- phers concerning judgment, of which I think it unneceffary to fay much.
Mr. Hume fometimes adopts Mr. Locke's opinion, that it is the perception of the agree- ment or difagreement of our ideas; fometimes he maintains, that judgment and reafoning re- folve themfelves into conception, and are no- thing but particular ways of conceiving objects; and he fays, that an opinion or belief may mod accurately be defined, a lively idea related to or ajfociated with a prefent imprejjion, Treatife of Human Nature, vol. i. page 172.
I have endeavoured before, in the firfl: chap- ter of this ElTay, to fhew that judgment is an operation of mind fpecifically diilincl from the bare conception of an objedt. I have alfo con- fidered his notion of belief, in treating of the theories concerning memory.
Dr. Hartley fays, " That aiTent and " dilfent muft come under the notion of ideas, " being only thofe very complex internal feel- " ings which adhere by alTociation to fuch " clufters of words as are called propofitions " in general, or affirmations and negations in " particular.'* This, if 1 underfland its meaning, agrees with the opinion of Mr. Hume above men- tioned.
SENTIMENTS concer7iiMg JUDGMENT. 237 tioned, and has therefore been before con- C H A P, fidered. ^. _"L Dr. Priestly has given another definition of judgment. " It is nothing more than the " perception of the univerfal concurrence, or " the perfect coincidence of two ideas; or the '' want of that concurrence or coincidence.^* '' This I think coincides with Mr. Locke's de- " finition, and therefore has been already *' confidered."
There are many particulars which deferve to be known, and which might very properly be confidered in this Effay on judgment; concern- ing the various kinds of proportions by which our judgments are expreiTed; their fubjefts and predicates; their converfions and oppofi- tions: But as thefe are to be found in every fyftem of logic from^ Aristotle down to the prefent age, I think it unneceiTary to fwell this Eiiay with the repetition of what has been faid fo often. The remarks which have occurred to me upon what is commonly faid on thefe points, as well as upon the art of fyllogifm; the utility of the fchool logic, and the improve- ments that may be made in it, may be found in a Short account (&/" Aristotle's Logic with Re/Jiarks, which Lord Kaimes has honoured with a place in his Sketchet of the Hijlory of Man, CHAP.
ESSAY VL CHAP. IV.
Of Jirji Principles in General.
N E of the moft Important diftin^lions of our judgments is, that feme of them are intuitive, others grounded on argument.
It is not in our power to judge as we wilL The judgment is carried along neceflarily by the evidence, real or feeming, which appears to us at the time. But in propofitions that are fubmitted to our judgment, there is this great difference; fome are of fuch a nature that a man of ripe underftanding may apprehend them diftinftly, and perfedly underftand their mean- ing without finding himfelf under any neceffity of believing them to be true or falfe, probable or improbable. The judgment remains in fuf- pence, until it is inchned to one fide or another by reafons or arguments.
But there are other propofitloiis which are no fooner underftood than they are believed. The judgment follows the apprehenfion of them neceffarily, and both are equally the work of nature, and the refult of our original powers. There is no fearching for evidence, no weigh- ing of arguments; the propofition is not dedu- ced or inferred from another; it has the light of truth in itfelf, and has no occafion to bor- row it from another.
Propofitions of the laft kind, when they are ufed in matters of fcience, have commonly been called axioms; and on whatever occafion they are ufed, are called^r/? principles, princi- ples of common fenfe, common notions, felf -evident truths.
Of FIRST PRINCIPLES in GENERAL. 239 truths. Cicero calls them Natura: jiidicia^dri A?, judicia communibus hominum fcnfihus infix a. ^"* Lord Shaftesbury exprelTes them by the ^ ' words, natural knowledge^ fundamental reafon, and common fenfe.
What has been fald, I think, is fufficient to diftinguifti firft principles, or intuitive judg- ments, from thole which may be afcribed to the power of reafoning; nor is it a jufl objec* tion againfl this diftinclion, that there may be fome judgments concerning which we may be dubious to which clafs they ought to be refer- red. There is a real diftindtion between per- fons within the houfe, and thofe that are with- out; yet it may be dubious to which the man belongs that flands upon the threfhold.
The power of reafoning, that is of drawing a conclufion from a chain of premifes, may with fome propriety be called an art. " All " reafoning,'* fays Mr. Locke, " is fearch " and carting about, and requires pains and " application." It refembles the power of walking, which is acquired by ufe and exer- cife. Nature prompts to it, and has given the power of acquiring it; but mull be aided by frequent exercife before we are able to walk. After repeated efforts, much {fumbling, and many falls, we learn to walk; and it is in a fmiilar manner that we learn to reafon.
But the power of judging in felf-evident pro- pofitions, which are clearly underftood, may be compared to the power of fwallowing our food. It is purely natural, and therefore com- mon to the learned, and the unlearned; to the trained, and the untrained: It requires ripenefs of underftanding, and freedom from prejudice, but nothing elfe.
I take r4c ESSAY VI.
I take it for granted, that there are felf-evi- dent principles. Nobody, I think, denies it. And if any man were fo fceptical as to deny that there is any propofition that is felf-evident, I fee not how it would be pofTible to convince him by reafoning.
But yet there feems to be great difference of opinions among Philofophers about firft prin- ciples. What one takes to be felf-evident, another labours to prove by arguments, and, a third denies altogether.
Thus, before the time of Des Cartes, it was taken for a firfl principle, that there is a fun and a moon, an earth and fea, which re- ally exift, whether we think of them or not. Des Cartes thought that the exiflence of thofe things ought to be proved by argument; and in this he has been followed by Male- BRANCHE, Arnauld, and Locke. They have all laboured to prove, by very weak rea- foning, the exiitence of external objeds of fenfe; and Berkeley and Hume, fenfible of the weaknefs of their arguments, have been led to deny their exiftence altogether.