自由是法律允许的一切权利。
In mathematics, the art of proposing a question must be held of higher value than solving it.
创造力不仅仅是拥有新想法,而是使这些想法具有实际用途。
数学思想的真正考验是它能否激发进一步的思考。
Sustainability isn't a cost—it's an investment in our future.