Orison Swett Marden：Pushing to the Front, Excerpt 115

See Kepler struggling with poverty and hardship, his books burned in public by order of the state, his library locked up by the Jesuits, and himself exiled by public clamor. For seventeen years he works calmly upon the demonstration of the great principles that planets revolve in ellipses, with the sun at one focus; that a line connecting the center of the earth with the center of the sun passes over equal spaces in equal times, and that the squares of the times of revolution of the planets above the sun are proportioned to the cubes by their mean distances from the sun. This boy with no chance became one of the world's greatest astronomers.

Source： https://www.gutenberg.org/ebooks/21291
Locator：Excerpt 115 · Verified：2026-10-19 · Verification：Short excerpt

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