โ Scribed by Frank Wesley
No coin nor oath required. For personal study only.
As we gather more historical details the Zeitgeist rather than the man seems to gain in importance. Verhave5 for instance, has recently shown that the behavioristic philosophy of Thorndike and Watson was ably expressed by the American philosopher, editor, and inventor, Joseph Buchanan as early as 1812. Watson had another forerunner, Raehlmann 2, who proposed behavioristic axioms in 1890 and reported an infant conditioning experiment in 1903.
Professor E. Raehlmann, a German ophthalmologist, was interested in the developmental aspects of color vision. In the latter part of the 18th Century when scientists adhered to the dictum "ontogeny recapitulates phylogeny" it was assumed that the capacity to recognize colors does not develop before the fourth year of life and only after such visual attributes as motion, form, depth and brightness can be perceived. It is interesting to note that these assumptions were made by the intellectual avant guard of the day who had accepted Darwinism. Empirical investigations conducted by Preyer, Magnus, Cohn, Roselli4 and others found no evidence of color discrimination before the third or fourth years, thus supporting the rational assumptions.
Raehlmann criticized the verbal criterion used by the above experimenters. A child, he hypothesized, may perceive color differences quite early, but may not be able to associate the correct verbal response, the name of the color, with its respective stimulus until it is several years old. Raehlmann therefore suggested in 1890 that the child's Greifbewegung (grasping, reaching motion) should be observed and not his verbal response.
To test his hypothesis Raehlmann gave infants bottles which were identical except for their color. He first made all bottles opaque so his subjects could not detect which of two bottles contained milk. He then painted one bottle green, the other red, equalizing for brightness by applying the paint and inspecting the bottles under a smoked glass. Both bottles were always presented simultaneously in alternating positions. For some infants the red bottle was always filled with milk? the green one being empty. For others the green bottle was always filled with the red one always empty.
Raehlmann found that some children could learn to reach for the correct bottle by the age of six months, perhaps soon after they were physically capable of reaching and hand stretching. Learning occurred through trial and error. Once established the performance remained at the 100 per cent correctness level. Discrimination was obtained along the entire spectrum. The performance of boys did not differ from that of girls. Raehlmann attributed individual differences to intelligence. He thought that he was successful in finding an earlier age level because he reinforced the actual response involved; while other experimenters were unsuccessful because they had tested for an association between a color and its name, an association which was never directly and at best only socially rewarded. Raehlmann compares the need of his infant subjects to those of myopic patients who lack
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