And never been applied to the organ. A LAPLANDER OF There is, however, one contradi&ory phænomenon, which may prove, that it is not abfolutely impoffible for ideas to arife, independent of their correfpondent impreffions. I believe it will readily be allowed, that the feveral diftinct ideas of colour, which enter by the eye, or thofe of found, which are conveyed by the ear, are really different from each other; though, at the fame time, refembling. Now if this be true of different colours, it must be no lefs fo of the different fhades of the fame colour; and each fhade produces a diftinct idea, independent of the reft. For if this fhould be denied, it is poffible, by the continual gradation of fhades, to run a colour infenfibly into what is most remote from it; and if you will not allow any of the means to be different, you cannot, without abfurdity, deny the extremes to be the fame. Suppofe, therefore, a perfon to have enjoyed his fight for thirty years, and to have become perfectly acquainted with colours of all kinds, except one particular fhade of blue, for inftance, which it never has been his fortune to meet with. Let all the different fhades of that colour, except that fingle one, be placed before him, de fcending fcending gradually from the deepeft to the lighteft; it is plain, that he will perceive a blank, where that fhade is wanting, and will be fenfible, that there is a greater diftance in that place between the contiguous colours than in any other. Now I afk, whether it be poffible for him, from his own imagination, to fupply this deficiency, and raife up to himfelf the idea of that particular fhade, though it had never been conveyed to him by his fenfes ? I believe there are few but will be of opinion that he can: And this may ferve as a proof, that the fimple ideas are not always, in every inftance, derived from the correfpondent impreffions; though this inftance is fo fingular, that it is fcarcely worth our obferving, and does not merit, that for it alone we should alter our general maxim. All Here, therefore, is a propofition, which not only feems, in itself, fimple and intelligible; but, if a proper ufe were made of it, might render every dispute equally intelligible, and banish all that jargon, which has fo long taken poffeffion of metaphytical reafonings, and drawn difgrace upon them. ideas, efpecially abftract ones, are naturally faint and obfcure: The mind has but a flender hold of them: They are apt to be confounded with other refcmbling ideas; and when we have often employed any term, though without a diftinct meaning, we are apt to imagine it has a determinate idea annexed to it. On the contrary, all impreffions, that is, all fenfations either outward or inward, are ftrong and vivid: The limits between them are more exactly determined: Nor is it easy to fall into any error or miflake with regard to them. When we entertain, therefore, any fufpicion, that a philofophical term is employed without any meaning or idea (as is but too frequent), we need but enquire, from what impreffion is that fuppofed idea derived? And if it be impoffible to affign any, this will ferve to confirm our fufpicion. VOL. II. By By bringing ideas into fo clear a light, we may rea fonably hope to remove all difpute, which may arife, concerning their nature and reality *. SECTION III. Of the AssOCIATION of IDEAS. T is evident, that there is a principle of connec tion between the different thoughts or ideas of the mind, and that, in their appearance to the memory or imagination, they introduce each other with a certain degree of method and regularity. In our more serious thinking or difcourfe, this is fo obfervable, that any particular thought, which breaks in upon the regular tract or chain of ideas, is immediately remarked and rejected. And even in our wildest and most wandering reveries, nay in our very dreams, we fhall find, if we reflect, that the imagination ran not altogether at adventures, but that there was ftill a connection upheld among the different ideas which fucceeded each other. Were the looseft and freeft converfation to be tranfcribed, there would immediately be observed fomething which connected it in all its tranfitions. Or where this, is wanting, the person who broke the thread of discourse, might ftill inform you, that there had fecretly revolved in his mind a fucceffion of thought, which had gradually led him from the fubject of converfation. Among different languages, even where we cannot fufpect the leaft connection or communication, it is found, that the words, expref See NOTE [A]. five five of ideas, the moft compounded, do yet nearly correspond to each other: A certain proof, that the fimple ideas, comprehended in the compound ones, were bound together by fome univerfal principle, which had an equal influence on all mankind. Though it be too obvious to escape observation, that different ideas are connected together; I do not find, that any philofopher has attempted to enumerate or class all the principles of affociation; a suba ject, however, that feems worthy of curiofity. To me, there appear to be only three principles of connection among ideas, namely, Refemblance, Contiguity in time or place, and Caufe or Effect. That these principles ferve to connect ideas will not, I believe, be much doubted. A picture naturally leads our thoughts to the original*: The mei tion of one apartment in a building naturally introduces an enquiry or discourse concerning the othersf: And if we think of a wound, we can fcarcely forbear reflecting on the pain which follows it f. But that this enumeration is complete, and that there are no other principles of affociation except these, may be difficult to prove to the fatisfaction of the reader, or even to a man's own fatisfaction. All we can do, in such cases, is to run over several instances, and examine carefully the principle which binds the different thoughts to each other, never ftopping till we render the principle as general as poffible §. The more inftances we examine, and the more care we employ, the more affurance fhall we acquire, that the enumeration, which we form from the whole, is complete and entire. * Refemblance: C 2 + Contiguity: SECTION Cause and Effect. § For inftance, Contraft or Contrariety is alfo a connection among Ídeas: But it may, perhaps, be confidered as a mixture of Caufation and Refemblance. Where two objects are contrary, the one destroys the other; that is, the caufe of its annihilation, and the idea of the annibilation of an object, implies the idea of its former existence. (36) SECTION IV. SCEPTICAL DOUBTS concerning the OPERATIONS of the UNDERSTANDING, PART I. LL the objects of human reafon or enquiry may A naturally be divided into two kinds, to wit, Relations of Ideas, and Matters of Fact. Of the firft kind are the sciences of Geometry, Algebra, and Arithmetic; and in fhort, every affirmation which is either intuitively or demonftratively certain. That the fquare of the hypothenufe is equal to the fquare of the two fides, is a propofition which expreffes a relation between thefe figures. That three times five is equal to the half of thirty, expreffes a relation between thefe numbers. Propofitions of this kind are difcoverable by the mere operation of thought, without dependance on what is any where exiftent in the univerfe. Though there never were a circle or triangle in nature, the truths demonftrated by EUCLID Would for ever retain their certainty and evidence. Matters of fact, which are the second objects of human reafon, are not ascertained in the fame manner; nor is our evidence of their truth, however great, of a like nature with the foregoing. The contrary of every matter of fact is ftill poflible; because it can never imply a contradiction, and is conceived by the mind with the fame facility and diftinctnefs, as if ever fa |