Who can not be independent, who can not talk about freedom.
谁若不能独立，谁就谈不上自由。
The ratio of positive to negative emotions that predicts flourishing is about 3 to 1. Above that ratio, people tend to flourish; below it, they tend to languish.
The goal of mathematics is not to solve problems, but to understand them.
Never underestimate the power of a well-designed experiment.