Without theory, practice is but routine born of habit. Theory alone can bring forth and develop the spirit of invention. ... [Do not] share the opinion of those narrow minds who disdain everything in science which has not an immediate application. ... A theoretical discovery has but the merit of its existence: it awakens hope, and that is all. But let it be cultivated, let it grow, and you will see what it will become.
Interpretation
Theory is essential for true innovation and understanding in science, while practice alone may lead to monotonous habits.
This quote by Louis Pasteur emphasizes the importance of theory in the realm of scientific practice. He argues that while practical skills are important, they can become mere routines without the guidance and inspiration that theory provides. Pasteur warns against dismissing theoretical discoveries as irrelevant or useless, as they can spark hope and lead to significant advancements when nurtured properly. In essence, he advocates for a balance between theory and practice in the pursuit of knowledge and innovation.
In practice
In a science class discussing the importance of theory in experiments, this quote can inspire students to value theoretical knowledge.
To demonstrate experimentally that a microscopic organism actually is the cause of a disease and the agent of contagion, I know no other way, in the present state of Science, than to subject the microbe (the new and happy term introduced by M. Sédillot) to the method of cultivation out of the body.
The universe is an asymmetrical entity. I am inclined to believe that life as it is manifested to us must be a function of the asymmetry of the universe or of the consequence of this fact. The universe is asymmetrical; for if one placed the entire set of bodies that compose the solar system, each moving in its own way, before a mirror, the image shown would not be superimposable on the reality.
These are the living springs of great thoughts and great actions. Everything grows clear in the reflections from the Infinite.
These three things-work, will, success-fill human existences. Will opens the door to success, both brilliant and happy. Work passes these doors, and at the end of the journey success comes in to crown one's efforts.
Chance favors those who are prepared.
You bring me the deepest joy that can be felt by a man whose invincible belief is that Science and Peace will triumph over Ignorance and War, that nations will unite, not to destroy, but to build, and that the future will belong to those who will have done most for suffering humanity.
When a scientist is ahead of his times, it is often through misunderstanding of current, rather than intuition of future truth. In science there is never any error so gross that it won't one day, from some perspective, appear prophetic.
We must trust to nothing but facts: These are presented to us by Nature, and cannot deceive. We ought, in every instance, to submit our reasoning to the test of experiment, and never to search for truth but by the natural road of experiment and observation.
Burning fossil fuels emits carbon dioxide. And carbon dioxide is a greenhouse gas that traps heat in the atmosphere. There is no debate about that. The link is as certain as the link between smoking and cancer.
What I like about sceptics is that in good science you need critics that make you think: 'Crumbs, have I made a mistake here?' If you don't have that continuously, you really are up the creek. The good sceptics have done a good service, but some of the mad ones I think have not done anyone any favours.
There are, in truth, no specialties in medicine, since to know fully many of the most important diseases a man must be familiar with their manifestations in many organs.
Science is not a substitute for common sense, but an extension of it.
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