Page:On the Fourfold Root, and On the Will in Nature.djvu/37

 their reason. So it was long ago observed by Plato: καί γὰρ αί δόξαι αί ἀληθείς ού πολλού ᾶἕιαί είσιν, ἔως ᾶν τις αύτὰς δήοη αίτίας λογισμῳ (etiam opiniones veræ non multi pretii sunt, donec quis illas ratiocinatione a causis ducta liget). Nearly every science, moreover, contains notions of causes from which the effects may be deduced, and likewise other notions of the necessity of conclusions from reasons, as will be seen during the course of this inquiry. Aristotle has expressed this as follows: πᾶσα ἐπιστήμη διανοητική, ἢ καί μετέχουσά τι διανοίας, περί αίτίας καί ἀρχάς ἐστι (omnis intellectualis scientia, sive aliquo modo intellectu, participans, circa causas et principia est.) Now, as it is this very assumption a priori that all things must have their reason, which authorizes us everywhere to search for the why, we may safely call this why the mother of all science.

§ 5. The Principle itself.
We purpose showing further on that the Principle of Sufficient Reason is an expression common to several a priori notions. Meanwhile, it must be stated under some formula or other. I choose Wolf's as being the most comprehensive : Nihil est sine ratione cur potius sit, quam non sit. Nothing is without a reason for its being.