However, Korzybski's principal means to accomplish extensionalization in our semantic (non-verbal) reactions wasn't to change the language, but to train us to visualize the horizontal and vertical structure of human knowledge. (S&S p469)
In his first two papers on general semantics ("Time Binding: The General Theory") Korzybski wrote not one word about abolishing the is of identity or other forms of "to be." Nor did he mention the "extensional devices" (indexes, dates, quotation marks ...). He did spend much time explaining the Structural Differential, which in the mid 1920s he called the Anthropometer.
Korzybski spent a few pages in Science and Sanity warning about the misleading implications of some usages of "to be" and suggesting the use of extensional devices to help us properly evaluate. But he devoted nearly a third of S&S to an explanation of the Structural Differential and the importance of learning to visualize our knowledge.
"Visualization requires a definite elimination, through differentiation, of harmful identification, which, as usual, is based on incorrect evaluation of structural issues." (S&S p453)
"The most effective means to transform the s.r. of identification is found in visualization, which indicates its special semantic importance." (S&S p460)
"The training in visualization and the abolishing of objectification are the first and most important steps for a complete elimination of identification. When this first step is achieved, the rest is comparatively a very simple task." (S&S p468)
"It seems that the first step in developing a method to accomplish these ends is to use the Structural Differential, without which it is practically impossible to teach 'silence on the objective level' and 'delayed action' and to train through all centers in non-identity, 'stratification,' natural order, and so in appropriate s.r." (S&S p446)
And from Korzybski's last published paper written in 1950:
"... when we 'think' without words, or in pictures or visualizations (which involve structure and, therefore, relations), we may discover new aspects and relations on silent levels, and so may formulate important theoretical results in the general search for a similarity of structure between the two levels, silent and verbal. Practically all important advances are made in that way." (Korzybski's Collected Writings p690)
At home I have a poster of the Structural Differential sent to me by the Institute. I have a copy of the SD from page 396 of S&S (pictured here) in my office. I have developed my own version of the Structural Differential that you find atop my gs home page. Their presence stimulates others to ask me to explain them. I long ago took Korzybski's advice 'to heart' and learned to visualize his, as well as others, theories. I encourage my students to do the same.