1. Enthusiasm without knowledge is like an expedition in the dark. Newton.

2. My life experience makes me believe that people who have no shortcomings often have few advantages. Lincoln.

3. Everything is born of competition and need. (ancient Greece) Heraclitus.

4. Natural selection is bound to come. If it is not good, it will be bad, and if it is not prosperous, it will die. Liang Qichao (China's modern enlightenment thinker).