This is his opinion of experimental psychology:
In psychology we are studying the most modern experimental researches. At present we are engaged upon Thought and Imagination. I must confess that I do not find this course very illuminating, though I agree that it is necessary to know something of these researches. In modern psychology there is nothing at all adequate to the subject of our method. These investigators seem to me like persons looking at a tree, and noting the most obvious of its external forms: the shape of a leaf, a stem, etc., doing all this with great gravity and using very precise language (perhaps believing that this constitutes science), but often confusing the function of definition with that of description.
In this manner descriptions of wonderful and fascinating things are reduced to arid definitions, in order to be clothed in their science, and thus are rendered powerless to inspire thought. They never meditate; they read a great deal; they think in mental images which no more represent facts than a diagram on the blackboard represents a living organ; and these images differ among different psychologists, but their language is always the same. They do all this believing they are making progress, and instead of training their pupils to observe for themselves without prejudice, they instil their own prejudices into the minds of the students, cramming them with definitions and descriptions of the strangest and most amorphous kind, which effectually prevent them from thinking for themselves.
But within the tree there is the fundamental structure which they have not begun to examine, though the revelation of this would explain all the external data. The details would diminish in importance; all these details issuing from a single root might be classified in the simplest manner. This "science" reminds me of that antiquated lore which dealt with the constellations, when the laws of planetary motion were not yet known, and the so-called science confined itself to descriptions of the "Great Bear," the "Crab," the "Goat," etc.
I detest those dryasdusts who, unaware of their own ignorance, write enormous arid tomes with an air of great majesty, as if they were revealing absolute knowledge, books that lie heavy on the minds of the students, making them dry as their teachers. But the students seem to me to care only about passing their examinations and to have no thought of discovering new knowledge; and the professors "serve" them to this end. Thus we are all in a state of servitude due to a mistaken system of education, which calls loudly for reform.