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Two simple questions related to the phrase "science proper" in the following sentence by Albert Einstein:
As long as we remain with the realm of science proper, we never meet with a sentence of the type "Thou shalt not lie".
Is "science proper" literally equal to "proper science"? (I mean after neglecting the history of the phrase "science proper" in philosophy)
Does "proper" here literally mean genuine?
For those who might be interested in philosophy, I should add that he is talking here about the is-ought problem.