No. 3 was kept in a cage not half so big as those of 1 and 2. Perhaps because of the hindrance this fact offered to forming the habit of reacting in some definite way to ‘yes’ signals, perhaps because of the fact that I did not try hand movements as signals, there was no successful discrimination by No. 3 of the yellow from the black diamond or of a card with YES from a card with a circle on it. I tried climbing up to a particular spot as the response to the ‘yes’ signal and staying still as the response to the ‘no’ signal. I also tried instead of the latter a different act, in which case the animal was fed after both signals but in different places. In the latter case No. 3 made some progress, but for practical reasons I postponed experiments with him. Circumstances have made it necessary to postpone such experiments indefinitely.
EXPERIMENTS WITH NO. 3
From Animal Intelligence: Experimental Studies by Edward L. Thorndike.
