The word “real” (from the Latin “res” = thing) was coined in the 13th century to signify “having Properties” (Pierce. 1958, p. 358), whereas a “model” refers to an analogical representation, the structure of which should correspond to the structure or properties of that which it represents. For Scudder the mind is a system of models and each mind develops different models. We all have a different reality in mind and so we each live in a slightly different world (Scudder, (...) 1975). Hence the real nature of the model and the model nature of reality are often indistinguishable. A snail, for example, when exposed to four tactile stimuli per second (with a rod on his belly) will be compelled to crawl upon that non-existing coherent spatial surface (Brecher, 1966). For the snail four tactile stimuli per second correspond to, or are isomorphic with, the structure of a spatial surface, but it is impossible for the snail to “know” which of the two structures is real. (shrink)