tes' Lehre von den angeborenen
Ideen_, 1873; G. Glogau, _Darlegung und Kritik des Grundgedankens der
Cartesianisch. Metaphysik (Zeitschrift fuer Philosophie_, vol. lxxiii. p.
209 _seq_.), 1878; Paul Natorp, _Descartes' Erkenntnisstheorie_, 1882;
and Kas. Twardowski, _Idee und Perception_ in Descartes, 1892. In French,
Francisque Bouillier (_Histoire de la Philosophie Cartesienne_, 1854) and
E. Saisset (_Precurseurs et Disciples de Descartes_, 1862) have written
on Cartesianism. [The _Method, Meditations, and Selections from the
Principles_ have been translated into English by John Veitch, 5th ed.,
1879, and others since; and H.A.P. Torrey has published _The Philosophy
of Descartes in Extracts from his Writings_, 1892 (Sneath's Modern
Philosophers). The English reader may be referred, also, to Mahaffy's
_Descartes_, 1880, in Blackwood's Philosophical Classics; to the article
"Cartesianism," _Encyclopedia Britannica_, 9th ed., vol. v., by Edward
Caird; and, for a complete discussion, to the English translation of
Fischer's _Descartes and his School_' by J.P. Gordy, 1887.--TR.]]

We begin our discussion with Descartes's noetical and metaphysical
principles, and then take up in order his doctrine of nature and of man.

%1. The Principles%.

That which passes nowadays for science, and is taught as such in the
schools, is nothing but a mass of disconnected, uncertain, and often
contradictory opinions. A principle of unity and certainty is entirely
lacking. If anything permanent and irrefutable is to be accomplished in
science, everything hitherto considered true must be thoroughly demolished
and built up anew. For we come into the world as children and we form
judgments of things, or repeat them after others, before we have come into
the full possession of our intellectual powers; so that it is no wonder
that we are filled with a multitude of prejudices, from which we can
thoroughly escape only by considering everything doubtful which shows the
least sign of uncertainty. Let us renounce, therefore, all our old views,
in order later to accept better ones in their stead; or, perchance, to
take the former up again after they shall have stood the test of rational
criticism. The recognized precaution, never to put complete confidence in
that which has once deceived us, holds of our relation to the senses as
elsewhere. It is certain that they sometimes deceive us--perhaps they do so
always. Again, we dream every day of things wh