利用 constant 和 variable 的反义对比，生动地阐述了主观努力对客观限制的影响。
The scientific level of a country can be measured by the amount of mathematics it consumes.
In the realm of mathematics, the art of posing questions is more important than the art of solving them. — Cantor
When discussing the secret of success, the greatest scientist of the modern era, Einstein, wrote the formula: A=x+y+z. He explained: A stands for success, x represents hard work, y represents the right method, and z represents saying less and doing more. — Einstein
Chinese scientist Wang Juzhen had a maxim regarding experimental failure: If you keep going, there is still hope for success; if you give up, it is a 100% failure.
Time is a constant, but for the diligent, it is a variable. Those who calculate time in minutes have more time than those who calculate it in hours... — Rebrov
一个国家的科学水平能够用它消耗的数学来度量。
在数学的领域中，提出问题的艺术比解答问题的艺术更为重要。——康托尔
近代最伟大的科学家爱因斯坦在谈成功的秘诀时，写下一个公式：A=x+y+z。并解释道：A代表成功，x代表艰苦的劳动，y代表正确的方法，Z代表少说空话。——爱因斯坦
我国科学家王菊珍对待实验失败有句格言，叫做干下去还有成功的期望，不干便是百分之百的失败。
时间是个常数，但对勤奋者来说，是个‘变数’。用‘分’来计算时间的人比用‘小时’来计算时间的人时间多若干倍……——雷巴柯夫
"Time is like water in a sponge—if you know how to squeeze it, there is always more available."
"If you do not run with time, you will eventually be left behind."
"Do not casually say you have no time; time is something you squeeze out."
"Time is like water in a sponge; if one is willing to squeeze, there is always some to be found."
"Where your time is spent, that is where your achievements lie."