Page:Cyclopaedia, Chambers - Volume 1.djvu/36

 PREFACE, xx iii

work, that fhould examine the feveral Dictionaries extant, by the Standard here laid down : None of them

could abide fuch a Trial ; even that here ottered muft go to wrack, like the reft.- It may be remembcr'd

that the Thing executed is allowed to come (hort of the Idea conceived : The former is only a Copy of the latter, and liable to all the Imperfections incident to other Copies. A thoufand things interfere : Lexicogra- phy, being of the Nature of an Art, deviates of cOurfe from what pure Reafon would prefcribe ; and its Pro- ductions come to degenerate ftill farther, by the Accidents that attend their bringing forth. The Tools, the Materials, and forty things come into the Account : the former prove out of order ; the latter obftinate, and untraceable, or perhaps not eafy to be had. In effeCt, the Author's Situation, his want of Leifure or Perfeve- rance, his Frailties and Foibles, nay his very Perfections and all, confpire againft it.

INDEED, a too fervile Attachment to the Rules and Methods of an Art, in many Cafes proves incommo- dious and impertinent. We know that the Rules of an Art are pofterior to the Art it felf ; and were taken from it or adjufted to it, after the thing it felf was done. An Author, therefore, is ftill in fome meafure left to his own Conduct, and may confider himfelf as inverted with a fort of difcretionary Power, whereby he can difpenfe with fome of 'em, and go by others of his own fuggefting, where he apprehends it for the ge- neral advantage of the Work. The Heights of Art are never to be reach'd by the Rules, but by Genius ; by reafon the Rules were accommodated to a certain Concourfe of Circumftances, which rarely happens twice ; fo that Laws ftiould be made de novo for every new Cafe, or Condition of things. While a Perfon confiders himfelf as following at fecond hand, the Meafures pointed out or prefcribed by others ; he will not go on with that Spirit and Alacrity, as when he follows his own Bent. He fhould therefore confider himfelf in the Place of the firft Inventor, or as his Reprefentative, or Succeffor ; and therefore qualified to enact with the fame Authority for the prefent occafion, as he did for another.

WHEN a Law is not founded on mere Reafon, as we have ihewn is the Cafe in Art -, the Obfervation of fuch Law cannot be enjoined on others. It may well obtain with refpeCt to the Perfon that firft eftablifh'd it, as being agreeable to his perfonal Reafon, ;', e. accommodated to his particular Combination of Genius, Situa- tion, and other Circumftances ; but can't extend to thofe in whom this Combination is different. Accordingly, Few Laws of Art are univerfal. Small matter by what Laws and Prefcripts a People is guided, provided they be led on to Happinefs -, or by what Courfe a VefTel fleers, if fhe do but make a prolperous Voyage.

WITH this View, in the prefent Work, we have taken all the Advantages the nature of the Thing would afford us ; and have frequently made our felves Delinquents againft ftriCt Rule, for our Reader's good. — A Dic- tionary, by our own ConfefTion, is to be a Hiftory ; and yet we have not kept fo clofe to that Form, as to abandon the Benefit of all others. In the bufinefs of Mathematicks, for inftance, the regular way is to re- late, of enumerate the feveral Matters belonging thereto, without inveftigating or demonftrating their truth : Demonftrations, ftriCtly (peaking, have nothing to do in a Dictionary, no more than anth ntick Inftruments, Declarations, ISc. in a Hiftory. To pretend to demonftrate the feveral Properties and Relations, e. g. of Lines, Angles, Numbers, &c. in a Dictionary, were an Indifcretion as great, as for an Hiftorian to produce Certificates, and Copies of Parifh Regifters, of the Births, Burials, Marriages, &c. of the feveral Perfons whofe Actions he relates.— -And yet, on fome extraordinary Occafions, we have not forbore to give Demonftrations •, where, for inftance, there was any thing very interefting, or important in 'em : A Practice which Hiftorians themfelves frequently give into -^ tho it be a conferred Irregularity, as it breaks in upon the Unity of the Narration, and accordingly gives their Work the Denomination of Mix'd Hiftory.

BUT we are far from the Views of fome DiCtionarifts, who think it incumbent on 'em to demonftrate every thing that is capable thereof. This is direCtly to forget their Quality ; to corrupt the Integrity of the Work mal a propos ; 'tis being licentious, and impertinent at the fame time, and difpenfing with the Rules to their own coft. How dear, e. g, muft a competent Demonftration of moft of Euclid's Propofitions be here purchafed ? Either the Reader muft be at the Pains of picking it piecemeal from out of twenty feveral parts of the Book, where the Alphabet has happen'd to caft it ; or the Author muft relinquifh the Advantages of a Dictionary, and deliver things together, that properly belong to fo many feveral places ; or there muft be a Repetition of the fame thing a dozen times over. And for what ? why, to make the DiSionary do the Bu- finefs of an Euclid's Elements ; which it is the unfitteft in the World for. You might with equal propriety make an ozier Bafket fupply the Office of a Pleafure-Boat ; or a Sword-pummel that of a Portmanteau, as Paracelfus is faid to have done.

WHEN a thing has been once regularly demoriftrated, it may be afiumed, or taken for granted : every- body perhaps may be concerned in the Truth of it; but not to fee the Truth of it. To make it a Principle to take nothing upon truft, would be as troublefome in the Sciences, as in Life ; and we muft remain for ever, both wretched, and ignorant. Not only Suppofirions, but even Errors, frequently lead us to Knowledge btherwife inacceflible. Mathematicians themfelves, who of all others keep moft to Demonftration, yet find themfelves under a frequent Neceffity of admitting and making ufe of things as true, which they do not fee to be fo ; and thus are fway'd, like other People, by Authority. A Perfon who makes ufe of the Equality of the Square of the Hypothenufe, to the Squares of the two Sides ; upon the Credit of Pythagoras, or Eu- clid's having demonftrated it ; does little more than what they themfelves do on many Occafions, who afiume and -make ufe of Propofitions they have no other evidence of, but the knowledge or remembrance of their having been demonftrated.

THE Cafe is much the fame with experimenting ; which ftands On the like footing as demonftrating. They are both neceffary in their kind ; the latter, as it leads on our Knowledge, the former as it follows, and fe- cures the Rear : But their ufe is to be reftrained to thefe Purpofes ; and may be difpens'd withal in Cafes where neither of thefe are concerned. A Perfon who would difcover any Point in Phyficks, or broach and efta- blifh any Point in Mathematicks, muft ufe 'em : But the Occafion is in great meafure private, and perfonal ; and does not extend to the Publick in the fame degree as the Knowledge of the DoCtrines themfelves. That is, the particular means by which a thing was firft come at, or is fhewn to be true, do not intereft us fo immediately as the Knowledge of the thing it felf, which might have arofe from various other means, and in other manners : A Man may know a thing in the way of Prefumption, of Opinion, of Surmife, of Authority, and forty other ways ; which, tho all much inferior and lefs excellent than the way of Demonftration, and Certainty ; yet we are glad of 'em on many occafions, and ufe 'em to good purpofe. Every degree of Knowledge is valuable. It would be an unreafonable, as well as an incommodious Sullennefs in us, to refufe all Light, except that of Noon-day. We find our Eafe and Happinefs frequently depend on the doing of things by Twilight, or even Moon-light, or the ftill more dubious Light of, perhaps, a Rufh or a Glow-worm.

PTTHAGORAS, in all probability, was not ignorant of the Equality of the Square of the Hypothe- nufe, &c. before he demonftrated it ; elfe, what fhould have led him to look for the Demonftration ? And the like may be laid of many of Mr. Boyle's Experiments. Plato even obferves, that " the very putting a Quef- " oon, implies fome Knowledge of the thing demanded ; fince without this we mould not know that what is " returned is an Anfwer."

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