Inconsistent Mathematics
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Inconsistent Mathematics
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Re: Inconsistent Mathematics
#2> Escher also actively collaborated with the English mathematician Roger Penrose.
What!!??
... OK. Somehow I always assumed that Escher lived in 1800s. But he lived (1898 – 1972) and he knew Penrose who is older than I thought (born 1931, 87 years old).
I suspected for a moment that the article was intentionally inconsistent, but it checks out.
Re: Inconsistent Mathematics
#3A related but more concise set-theoretic discussion is given here:
https://philosophy.stackexchange.com/questions/9741/what-are...