The total quantity of all the forces capable of work in the whole universe remains eternal and unchanged throughout all their changes. All change in nature amounts to this, that force can change its form and locality, without its quantity being changed. The universe possesses, once for all, a store of force which is not altered by any change of phenomena, can neither be increased nor diminished, and which maintains any change which takes place on it.
Interpretation
The universe's total energy remains constant, despite changes in its form or location.
This quote emphasizes the conservation of energy principle, asserting that while energy can transform from one form to another, the total amount remains unchanged. Hermann Von Helmholtz highlights that the forces at play in the universe are eternal and invariant, underlying all changes and phenomena, suggesting a fundamental law of nature which assures that the sum of energy is preserved regardless of its manifestations.
In practice
In a lecture about physics, you could quote this to explain the conservation of energy.
Isolated facts and experiments have in themselves no value, however great their number may be. They only become valuable in a theoretical or practical point of view when they make us acquainted with the law of a series of uniformly recurring phenomena, or, it may be, only give a negative result showing an incompleteness in our knowledge of such a law, till then held to be perfect.
Black is real sensation, even if it is produced by entire absence of light. The sensation of black is distinctly different from the lack of all sensations.
Whoever, in the pursuit of science, seeks after immediate practical utility, may generally rest assured that he will seek in vain.
Fortunately, there's another handy driver that has manifested itself throughout the history of cultures. The urge to want to gain wealth. That is almost as potent a driver as the urge to maintain your security. And that is how I view NASA going forward - as an investment in our economy.
I think it is a peculiarity of myself that I like to play about with equations, just looking for beautiful mathematical relations which maybe don't have any physical meaning at all. Sometimes they do._x000D_ _x000D_ At age 60.
In the past, there was active discrimination against women in science. That has now gone, and although there are residual effects, these are not enough to account for the small numbers of women, particularly in mathematics and physics.
The invention of the scientific method and science is, I'm sure we'll all agree, the most powerful intellectual idea, the most powerful framework for thinking and investigating and understanding and challenging the world around us that there is, and it rests on the premise that any idea is there to be attacked. If it withstands the attack then it lives to fight another day and if it doesn't withstand the attack then down it goes. Religion doesn't seem to work like that.
When the first humans reached Australia about 45,000 years ago, they quickly drove to extinction 90% of its large animals. This was the first significant impact that Homo sapiens had on the planet's ecosystem. It was not the last.
A commonsense interpretation of the facts suggests that a superintellect has monkeyed with physics, as well as with chemistry and biology, and that there are no blind forces worth speaking about in nature. The numbers one calculates from the facts seem to me so overwhelming as to put this conclusion almost beyond question.
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