1) Mathematics is the queen of science and number theory is the queen of mathematics. Gauss music can inspire or soothe feelings, painting can make people pleasing to the eye, poetry can impress people, philosophy can make people gain wisdom, science can improve material life, but mathematics can give them all. Klein
2) The essence of mathematics lies in freedom. -Cantor.
3) In the field of mathematics, the art of asking questions is more important than the art of answering questions. -Cantor.
4) No problem can touch people's emotions as deeply as infinity, and few other concepts can stimulate reason to produce rich thoughts as infinity, but no other concepts need to be clarified as infinity. -Hilbert (Hilbert)
5) Mathematics is an infinite science. Herman Weil
6) The problem is the heart of mathematics. -P.R. halmos
7) As long as a branch of science can raise a large number of questions, it is full of vitality, and no questions indicate the termination or decline of independent development. -Hilbert
8) Some beautiful theorems in mathematics have such characteristics: they are easy to be summarized from facts, but the proofs are extremely hidden. Gauss
9) Philosophers should also learn mathematics, because he must jump out of the vast phenomenon and grasp the real essence. ..... and because it is a shortcut for the soul to transition to truth and eternity. -Plato
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