Another good graphic from "A history of commerce, 1907" - before and after the age of explorers (mid-15th century).


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David Gelernter on a connection between creativity and emotion:
it's a general observation--that creativity often hinges on inventing new analogies. ... Now, what makes me come up with a new analogy? What allows me to do that? Generally, it's a lower-spectrum kind of thinking, a down-spectrum kind of thinking, in which I'm allowing my emotions to ( Read more... )

Going over Treatise of Intuitionist Logic, by JG Granstorm for the second time (see fig and text below):

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