I am reading the book by Morris Kline "Mathematics, the Loss of Certainty". It mentioned that irrational numbers, negative numbers and complex numbers lack logical basis. So, how to define logical basis? And how can we say a logical basis is sound?
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I have a feeling that the logical basis cannot be defined. Because we need logic to define something. And in this scenario, it is kind of like a vicious circle.
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Add some context from the google books:
