The moment a percept appears in my field of consciousness, thought, too, becomes active in me. A member of my thought-system, a definite intuition, a concept, connects itself with the percept. When, next, the percept disappears from my field of vision, what remains? The intuition, with the reference to the particular percept which it acquired in the moment of perception. The degree of vividness with which I can subsequently recall this reference depends on the manner in which my mental and bodily organism is working. An idea is nothing but an intuition related to a particular percept; it is a concept which was once connected with a certain percept, and which retains this reference to the percept. My concept of a lion is not constructed out of my percepts of a lion; but my idea of a lion is formed under the guidance of the percepts. I can teach someone to form the concept of a lion without his ever having seen a lion, but I can never give him a living idea of it without the help of his own perception. An idea is therefore nothing but an individualised concept. And now we can see how real objects can be represented to us by ideas. The full reality of a thing is present to us in the moment of observation through the combination of concept and percept. The concept acquires by means of the percept an individualised form, a relation to this particular percept. In this individualised form which carries with it, as an essential feature, the reference to the percept, it continues to exist in us and constitutes the idea of the thing in question. If we come across a second thing with which the same concept connects itself, we recognise the second as being of the same kind as the first; if we come across the same thing twice, we find in our conceptual system, not merely a corresponding concept, but the individualised concept with its characteristic relation to this same object, and thus we recognise the object again. The idea, then, stands between the percept and the concept. It is the determinate concept which points to the percept. The sum of my ideas may be called my experience. The man who has the greater number of individualised concepts will be the man of richer experience. A man who lacks all power of intuition is not capable of acquiring experience. The objects simply disappear again from the field of his consciousness, because he lacks the concepts which he ought to bring into relation with them. On the other hand, a man whose faculty of thought is well developed, but whose perception functions badly owing to his clumsy sense-organs, will be no better able to gain experience. He can, it is true, by one means and another acquire concepts; but the living reference to particular objects is lacking to his intuitions. The unthinking traveller and the student absorbed in abstract conceptual systems are alike incapable of acquiring a rich experience.