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.
Any scientist who can't explain to an eight-year-old what he is doing is a charlatan.
Mushrooms are miniature pharmaceutical factories, and of the thousands of mushroom species in nature, our ancestors and modern scientists have identified several dozen that have a unique combination of talents that improve our health.
[Concerning] the usual contempt with which an orthodox analytic group treats all outsiders and strangers ... I urge you to think of the young psychoanalysts as your colleagues, collaborators and partners and not as spies, traitors and wayward children. You can never develop a science that way, only an orthodox church.
Measure what is measurable, and make measurable what is not so.
Evolution has encountered no intellectual trouble; no new arguments have been offered. Creationism is a home-grown phenomenon of American sociocultural history-a splinter movement ... who believe that every word in the Bible must be literally true, whatever such a claim might mean.
What sense would it make or what would it benfit a physician if he discovered the origin of the diseases but could not cure or alleviate them?
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