Leaders rely on the future as a vaccine against the present. The Soviets have put a man in space? "I believe we should go to the moon," President Kennedy announces. "I have a dream," the Rev. Martin Luther King Jr. declares as the world around him burns. Maybe the promise is realized, even surpassed; maybe it keeps receding, pulling us along. "The best thing about the future is that it comes only one day at a time," Abraham Lincoln supposedly observed. Which is true for those in charge of creating it but maybe not for the rest of us. When we pause and look back, we get to see the past's future, know how the story turned out. Did we rise to the occasion? Did we triumph? Did we blink?

本段讲述恰恰是因为未来不可以预测，所以政治家往往靠它给人们不切实际的想象。第十题问道本段首句的句意，只需对本段进行总结即可。

The past's power comes from experience, the lessons it dares us to dismiss on the grounds that maybe things will be different this time. The future's power is born of experiment, and the endless grudge match between fear and hope. We are having a dozen simultaneous conversations right now about change: in our institutions, our culture, our treatment of the planet and of one another.

It's tempting to just stand stock-still and squeeze your eyes shut and wait for the moment to pass, or else hoard canned goods and assume the worst. This has been an awfully ugly summer of argument, and you'd be forgiven for concluding that we've lost our will to face or fix anything. We'll just dance with the devils we know, thank you. But if you look past Washington, past Wall Street, turn down the volume and go outside and walk around, you'll find the parcels of grace, of ingenuity and enterprise — people riding change like a skateboard, speeding off a ramp, twisting, flipping, somehow landing with a rush of wind and wheels — and wonder that it somehow hasn't killed us yet.

When members of the freshman class of 2027 look back at our future, what's likely to surprise them most? Will they marvel that gays were once not allowed to marry — or that they ever were? That we baited while the planet warmed, or that we acted to save it? That we protected the poor, or empowered them, or ignored them? That we lived within our means, or beyond them? We'll make our choices one day at a time, but our kids will judge our generation for what we generate, and what we leave undone.

8. Why does the author introduce the mindset list published by professor at Beloit College at the beginning of the passage?

9. What does the author mean by saying "our past's vision of the future was not visionary enough"?

10. Explain the sentence "Leaders rely on the future as a vaccine against the present." Make your comments.