SCIENCE AND SANITY - online book

An Introduction To Non-aristotelian Systems And General Semantics.

Home | About | Philosphy | Contact | Search

... in hypnotized children real colours and suggested colours are blended to form the complementary colour. (189)                          w. horsley gantt
Section A. Illustrations from biology.
Because of the semantic importance of the structural non-elemental-istic principle, and the weighty, yet in the beginning odd, consequences which follow the consistent application of this principle in practice, we will give a short account of some other experimental structural facts taken from widely separated fields.
A worm, a marine planarian, called a Thysanosoon (Brochii), is common in the bay of Naples. If we put a normal Thysanozoon on its back, it soon will right itself. When the brain of the worm has been removed, under similar conditions of the experiment, the worm will right itself, but more slowly. In this case, we see a general tendency of the organism-as-a-whole; the nervous system only facilitated a quicker action. If we cut the worm partly in two, so that the longitudinal nerves are severed, but a thin piece of tissue keeps the two parts together, the two parts move in a co-ordinated way, as if not cut. The organism still works as-a-whole, although the conditions seem not favourable.1
If we cut a fresh-water planarian (Planaria torva) in two, transversely, the posterior part, which has no brain, moves about as well as the anterior part, which has the brain. If we try to find the effect of light on the part devoid of brain and eyes, we see that the effect of light is not changed, and that the posterior part crawls away from light into dark corners as a normal animal would, except that the action takes place at a slower rate. In normal animals, the reaction usually begins in about one minute after the exposure; in the brainless part, it takes nearly five minutes of exposure.2
How chemical conditions affect the activities of the organism-as-a-whole can be well illustrated by the following examples. In a jellyfish, we can increase or decrease the locomotor activities by simply changing the chemical constitution of the water. If we increase the number of Na ions in the sea-water, the rhythmical contractions increase and the animal becomes restless. If we increase the number of Ca ions, the contractions decrease. In a similar way, we can change the orientation toward light in a number of marine animals by changing the constitution