A psychological consequence of this is the following: when we analyze a mechanism we tend to over estimate its complexity. - Valentino Braitenberg

Ad Aertsen succeeds in allowing his sense of humour to shine through the deep seriousness of his scientific ethos. He also has a very balanced attitude to the question of "theory or experiment".

The brain is encased in the head, the part of the body which in most walking, flying or swimming animals is the leading end of the moving body (with few exceptions: starfish, cuttlefish, humans, penguins when they are not swimming). The obvious risks which this localization entails are apparently compensated by the advantage of direct short connections with the sense organs localized in or on top of the head (olfaction, taste, vision, audition, vestibular sense), which together with the brain could be seen as something like the cockpit of the animal, or the pilot if one prefers.

A structure made up of fine threads, so many and so fine that even the strongest magnification of the microscope was hardly sufficient to allow all of them to be seen clearly. Some of the threads ran together in bundles and in layers in specific directions; others lay seemingly randomly distributed every which way through the tissue. Embedded in this felted mass of fibers, it was possible to discern spherical structures, the nuclei of the nerve cells...