Why, for example, what has been perceived many times is usually presented to the soul more clearly than what has been perceived only one or two times, and why the things one has seen and remembered more distinctly than those one has only imagined, which would explain, for example, why we would understand the distribution of the veins in the liver after seeing a dissection of this organ only once better than after reading it several times in an anatomy book, and so for other similar things.