Kepler and Newton represent a critical transition in humanhistory, the discovery that fairly simple mathematical laws pervade all of Nature; that the same rules apply on Earth as in the skies; and that there is a resonance between the way we think and the way the world works. They unflinchingly respected the accuracy of observational data, and their predictions of the motion of the planets to high precision provided compelling evidence that,
at an unexpectedly deep level, humans can understand the Cosmos. Our modern global civilization, our view of the world and our present exploration of the Universe are profoundly indebted to their insights. - P75
The principal energy sources of our present industrial civilization are the so-called fossil fuels.
We burn wood and oil, coal and natural gas, and, in the process, release waste gases, principally CO2, into the air. Consequently, the carbon dioxide contentof the Earth‘s atmosphere is increasing dramatically. The possibility of a runaway greenhouse effect suggests that we have to becareful: Even a one- or two-degree rise in the global temperature can have catastrophic consequences. In the burning of coal and oil and gasoline, we are also putting sulfuric acid into the atmosphere. Like Venus, our stratosphere even now has a substantial mist of tiny sulfuric acid droplets. Our major cities are polluted with noxious molecules. We do not understand the long-term effects of our course of action. - P106
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