The first mathematical crisis was the discovery of irrational numbers. Zhi Nuo put forward a famous paradox, revealing the difficulties encountered in the concepts of infinity and continuity.

B. The second mathematical crisis was the birth of calculus. People found the inaccuracy of Newton and Leibniz in calculus, especially whether infinitesimal is zero, which caused controversy.

C. The third mathematical crisis was in 1902 when Russell put forward Russell Paradox, which caused another argument in mathematics and shook the foundation of set theory.

D. After these three mathematical crises, mathematics has been quite perfect, and there will be no more crises.

Correct answer: ABC