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I myself, a professional mathematician, on re-reading my own work find it strains my mental powers to recall to mind from the figures the meanings of the demonstrations, meanings which I myself originally put into the figures and the text from my mind. But when I attempt to remedy the obscurity of the material by…
It is usual to say that the two sources of experience are Observation and Experiment. When we merely note and record the phenomena which occur around us in the ordinary course of nature we are said to observe. When we change the course of nature by the intervention of our will and muscular powers, and thus produce…
The next care to be taken, in respect of the Senses, is a supplying of their infirmities with Instruments, and, as it were, the adding of artificial Organs to the natural; this in one of them has been of late years accomplisht with prodigious benefit to all sorts of useful knowledge, by the invention of Optical…
When they [radio astronomers] grew weary at their electronic listening posts. When their eyes grew dim with looking at unrevealing dials and studying uneventful graphs, they could step outside their concrete cells and renew their dull spirits in communion with the giant mechanism they commanded, the silent, sensing…
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Every 12 years Jupiter returns to the same position in the sky; every 370 days it disappears in the fire of the Sun in the evening to the west, 30 days later it reappears in the morning to the east...
If experiments are performed thousands of times at all seasons and in every place without once producing the effects mentioned by your philosophers, poets, and historians, this will mean nothing and we must believe their words rather our own eyes? But what if I find for you a state of the air that has all the…
I, Galileo Galilei, son of the late Vincenzo Galilei, of Florence, aged seventy years, being brought personally to judgment, and kneeling before your Most Eminent and Most Reverend Lords Cardinals, General Inquisitors of the universal Christian republic against heretical depravity, having before my eyes the Holy…
The inventor and the research man are confused because they both examine results of physical or chemical operations. But they are exact opposites, mirror images of one another. The research man does something and does not care [exactly] what it is that happens, he measures whatever it is. The inventor wants something…
Human perception is rife with ways of getting things wrong. We don't like to admit it, because we have a high opinion of our biology, but it's true. Here's an example: We've all seen drawings that create optical illusions. They're lots of fun, but they should actually be called "brain failures." That's what's…
The astronomer is, in some measure, independent of his fellow astronomer; he can wait in his observatory till the star he wishes to observe comes to his meridian; but the meteorologist has his observations bounded by a very limited horizon, and can do little without the aid of numerous observers furnishing him…
I could not help laughing at the ease with which he explained his process of deduction. 'When I hear you give your reasons,' I remarked, 'the thing always appears to me to be so ridiculously simple that I could easily do it myself, though at each successive instance of your reasoning I am baffled, until you explain…
"Faith" is a fine invention When Gentlemen can see— But Microscopes are prudent In an Emergency.
In a discussion on my blog regarding teaching kids about death, one of my readers commented that he uses a book called Lifetimes, by Bryan Mellonie. He explained that the book describes the lifetimes of various living things and focuses on the life that happens in between birth and death. He explained, “I tell my kids…
In the Next Generation episode “Galaxy's Child,” the Enterprise stumbles upon an alien life-form that lives in empty space, feeding on energy. Particularly tasty is radiation with a very specific frequency 1420 million cycles per second, having a wavelength of 21 cm. In the spirit of Pythagoras, if there were a Music…
Almost 1000 years ago, Chinese astronomers observed a new star visible in the daytime sky, which they called a “guest star.” This supernova created what we now observe telescopically as the Crab Nebula. It is interesting that nowhere in Western Europe was this transient object recorded. Church dogma at the time…
In science, attempts at formulating hierarchies are always doomed to eventual failure. A Newton will always be followed by an Einstein, a Stahl by a Lavoisier; and who can say who will come after us? What the human mind has fabricated must be subject to all the changes—which are not progress—that the human mind must…
Wherever we seek to find constancy we discover change. Having looked at the old woodlands in Hutcheson Forest, at Isle Royale, and in the wilderness of the boundary waters, in the land of the moose and the wolf, and having uncovered the histories hidden within the trees and within the muds, we find that nature…
It is odd to think that there is a word for something which, strictly speaking, does not exist, namely, 'rest'. We distinguish between living and dead matter; between moving bodies and bodies at rest. This is a primitive point of view. What seems dead, a stone or the proverbial 'door-nail', say, is actually forever in…
I do not think that G. H. Hardy was talking nonsense when he insisted that the mathematician was discovering rather than creating, nor was it wholly nonsense for Kepler to exult that he was thinking God's thoughts after him. The world for me is a necessary system, and in the degree to which the thinker can surrender…