Gedankenexperiment

However, the subject need not be an esoteric one for a gedankenexperiment to be fruitful. My own favorite is Galileo’s proof that, contrary to Aristotle’s view, objects of different mass fall in a vacuum with the same acceleration. One might think that a real experiment needs to be conducted to test that hypothesis, but Galileo simply asked us to consider a large and a small stone tied together by a very light string. If Aristotle was right, the large stone should speed up the smaller one...

 Humanity is Like an Infant

Taking a very gloomy view of the future of the human race, let us suppose that it can only expect to survive for two thousand millions years longer, a period about equal to the past age of the earth. Then, regarded as a being destined to live for three-score years and ten, humanity although it has been born in a house seventy years old, is itself only three days old. But only in the last few minutes has it become conscious that the whole world does not centre round its cradle and its trapping...