In Science and Sanity, Alfred Korzybski memorably wrote:
The affairs of man [humankind] are conducted by our own, man-made rules and according to man-made theories. Man’s achievements rest upon the use of symbols. For this reason, we must consider ourselves as a symbolic, semantic [evaluational] class of life, and those who rule the symbols, rule us. (Science And Sanity, Fifth Ed., p. 76)
Independently of Korzybski, philosopher Ernst Cassirer also saw the defining importance of symbolism in understanding human life. Cassirer published the three volumes of his work, Philosophy of Symbolic Forms, in 1923-1929, a few years after Korzybski’s Manhood of Humanity. In a later work, An Essay on Man, Cassirer—apparently unaffected by Korzybski's work, although the two men had corresponded—wrote the following:
Man has, as it were, discovered a new method of adapting himself to his environment. Between the receptor system and the effector system, which are to be found in all animal species, we find in man a third link which we may describe as the symbolic system. This new acquisition transforms the whole of human life. As compared with the other animals man lives not merely in a broader reality; he lives so to speak, in a new dimension of reality.…Reason is a very inadequate term with which to comprehend the forms of man’s cultural life in all their richness and variety. But all these forms are symbolic forms. Hence, instead of defining man as an animal rationale, we should define him as an animal symbolicum. By so doing we can designate his specific difference, and we can understand the new way open to man––the way to civilization. (pp. 24-26)
Korzybski, who had carefully read Cassirer’s work, would differ from Cassirer in this way: he insisted from the time of his 1921 work Manhood of Humanity onwards, that this new psycho-biological way open to humanity, took humanity out of animal existence and merited its placement into an entirely new taxonomic "kingdom" of life—as time-binders. "Man", he repeated often, "is not an animal!"
In spite of this difference, not so little to Korzybski, he dedicated his book Science and Sanity to the works of Cassirer (1), among others, which “greatly influenced my enquiry.” Such scholarly acknowledgement was typical of Korzybski.
Also typically of Korzybski (trained as an engineer), he formulated the symbolic mechanism in terms of time-binding, in order to provide a practical way to apply Cassirer’s and others’ insights about human culture to living life—your life. In 1925 he wrote to Cassirer, then still in Germany,
As a engineer I am trying to formulate modes of action but this involves a host of theoretical issues, some as yet unresolved, and until the scientists scrutinize the theoretical issues, it will never become a mode of action. It seems to me that the conditions of the world are deeply upset mostly [due] to the exposure (destructive) of old doctrines, which were false and at present a lack of a general theory of human action... (Korzybski to Cassirer, April 28, 1925)
(1). Cassirer's books, Substance and Function and Einstein's Theory of Relativity, published in one volume in English by Open Court in 1923, affirmed Korzybski's general view of epistemology, and of all Cassirer's writings probably had the deepest effect on Korzybski.