the Discussions on Metaphysics and on Religion in 1688, and various polemic treatises.  The best known among the doctrines of Malebranche is the principle that we see all things in God (que nous voyons toutes choses en Dieu.—­Recherche, iii. 2, 6).  What does this mean, and how is it established?  It is intended as an answer to the question, How is it possible for the mind to cognize the body if, as Descartes has shown, mind and body are two fundamentally distinct and reciprocally independent substances?

The seeker after truth must first understand the sources of error.  Of these there are two, or, more exactly, five—­as many as there are faculties of the soul.  Error may spring from either the cognitive or the appetitive faculty; in the first case, either from sense-perception, the imagination, or the pure understanding, and, in the latter, from the inclinations or the passions.  The inclinations and the passions do not reveal the nature of things, but only express how they affect us, of what value they are to us.  Further still, the senses and the imagination only reproduce the impressions which things make on us as feeling subjects, express only what they are for us, not what they are in themselves.  The senses have been given us simply for the preservation of our body, and so long as we expect nothing further from them than practical information concerning the (useful or hurtful) relation of things to our body, there is no reason for mistrusting them,—­here we are not deceived by sensation, but at most by the overhasty judgment of the will.  “Consider the senses as false witnesses in regard to the truth, but as trustworthy counselors in relation to the interests of life!”—­Sensation and imagination belong to the soul in virtue of its union with the body; apart from this it is pure spirit.  The essence of the soul is thought, for this function is the only one which cannot be abstracted from it without destroying it.  Hence there can be no moment in the life of the soul when it ceases to think; it thinks always (l’ame pense toujours), only it does not always remember the fact.

The kinds of knowledge differ with the classes of things cognized.  God is known immediately and intuitively.  He is necessary and unlimited being, the universal, infinite being, being absolutely; he only is known through himself.  The concept of the infinite is the presupposition of the concept of the finite, and the former is earlier in us; we gain the conception of a particular thing only when we omit something from the idea of “being in general,” or limit it.  God is cogitative, like spirits, and extended, like bodies, but in an entirely different manner from created things.  We know our own soul through consciousness or inner perception.  We know its existence more certainly than that of bodies, but understand its nature less perfectly than theirs.  To know that it is capable of sensations of pain, of heat, of light, we must have experienced them.  For knowledge of the minds of others we are dependent upon conjecture, on analogical inferences from ourselves.