"The best way to learn mathematics is to do mathematics."

自然界的存在与任何命题的存在是同一类型的事实。

People should live according to the rhythm of nature.

La literatura es el único país donde puedo vivir sin pasaporte.

I always cheer up immensely if an attack is particularly wounding because I think, well, if they attack one personally, it means they have not a single political argument left.