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A mathematician's work is mostly a solitary pursuit, but it builds on the work of many others.

The mining industry has a responsibility to leave communities better than we found them.

In the infancy of societies, the chiefs of state shape its institutions; later the institutions shape the chiefs of state.

There are no hard distinctions between what is real and what is unreal, nor between what is true and what is false. A thing is not necessarily either true or false; it can be both true and false.