Prove All Things and Hold Fast to that which is Good

Notes the recurrence property of the Fibonacci numbers, starting with 0, and asserts that the ratio Fn+1/Fn approaches the ratio of segments of a line cut in mean and extreme ratio, i.e. φ, though he doesn't even give its value -- but he says 13, 13, 21 'rather precisely constitutes an isosceles triangle having the angle of a pentagon'. ................
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