假使人人都彼此爱护，则天下安治；倘若人人都彼此交恶，则天下大乱。墨家主张兼爱。兼爱，指同时爱不同的人或事物。墨子主张爱无差别等级，不分厚薄亲疏。
Sustainability isn't an option anymore - it's our responsibility to future generations.
The most profound discoveries in mathematics often come from questioning the most basic assumptions.
数学中最深刻的发现往往来自于对最基本假设的质疑。