"The goal is not to mourn the lost futures, but to use them as a resource for the struggle to come."

数学不是观赏性运动，你必须参与其中才能理解。

The present state of the system of nature is evidently a resultant of what it was in the preceding moment, and if we conceive of an intelligence which at a given instant comprehends all the relations of the entities of this universe, it could state the respective positions, motions, and general effects of all these entities at any time in the past or future.