&quot; Clear and distinct ideas are terms which, though familiar and frequent in 

 men s mouths, I have reason to think every one who uses does not perfectly 

 understand. And possibly it ia but here and there one who gives himself 

 the trouble to consider them so far as to know what he himself or others precisely 

 mean by them ; I have, therefore, in most places, chose to put determinate or 

 determined, instead of clear and distinct, as more likely to direct men s thoughts 

 to my meaning in this matter.&quot; LOCKE S Essay on the Human Understanding ; 

 Epistle to the Reader. 



&quot;II ne peut y avoir qu une me&quot;thode parfaite, qui est la mtthode naturelle; 

 on nomine ainsi un arrangement dans lequel les etres du merne genre seraient 

 plus voisins entre eux que ceux de tous les autres genres ; les genres du 

 meme ordre, plus que ceux de tous les autres ordres ; et ainsi de suite. 

 Cette me thode est l ide&quot;al auquel 1 histoire naturelle doit tendre ; car il est 

 Evident que si 1 on y parvenait, Ton aurait 1 expression exacte et complete de la 

 nature entiere.&quot; CDVIER, R&gne Animal, Introduction. 



&quot; Deux grandes notions philosophiques dominent la theorie fondamentale 

 de la methode naturelle proprement dite, savoir la formation des groupes 

 naturels, et ensuite leur succession hie rarchique.&quot; CoiiTE, Cows de Philosophic 

 Positive, 42meleson. 



