A good mathematician is someone who can see analogies between theorems; a great mathematician is someone who can see analogies between analogies.
一個好的數(shù)學(xué)家是能看到定理之間類比的人;一個偉大的數(shù)學(xué)家是能看到類比之間的類比的人。
Sustainability is no longer an option; it's a necessity for the future of leather tanning.