I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind.— Lord Kelvin
The most sensual Lord Kelvin quotes that are easy to memorize and remember
If you can not measure it, you can not improve it.
There is nothing new to be discovered in physics now.
All that remains is more and more precise measurement.
Heavier-than-air flying machines are impossible.
Radio has no future." "X-rays are clearly a hoax". "The aeroplane is scientifically impossible.
When you can measure what you are speaking about, and express it in numbers, you know something about it.
Large increases in cost with questionable increases in performance can be tolerated only in race horses and fancy women.
All science is either physics or stamp collecting.
Fourier is a mathematical poem.
Accurate and minute measurement seems to the non-scientific imagination, a less lofty and dignified work than looking for something new. But nearly all the grandest discoveries of science have been but the rewards of accurate measurement and patient long-continued labour in the minute sifting of numerical results.
The more thoroughly I conduct scientific research, the more I believe that science excludes atheism.
Suppose that you could mark the molecules in a glass of water;
then pour the contents of the glass into the ocean and stir the latter throughly so as to distribute the marked molecules uniformly throughout the seven seas; if then you took a glass of water anywhere out of the ocean, you would find in it about a hundred of your marked molecules.
I need scarcely say that the beginning and maintenance of life on earth is absolutely and infinitely beyond the range of all sound speculation in dynamical science. The only contribution of dynamics to theoretical biology is absolute negation of automatic commencement or automatic maintenance of life.
All of science can be divided into physics and stamp-collecting.
Vortices of pure energy can exist and, if my theories are right, can compose the bodily form of an intelligent species.
Overwhelmingly strong proofs of intelligent and benevolent design lie around us.
.. the atheistic idea is so nonsensical that I cannot put it into words.
Mathematics is the only good metaphysics.
The only census of the senses, so far as I am aware, that ever before made them more than five, was the Irishman's reckoning of seven senses. I presume the Irishman's seventh sense was common sense; and I believe that the possession of that virtue by my countrymen-I speak as an Irishman.
Quaternions came from Hamilton after his really good work had been done, and though beautifully ingenious, have been an unmixed evil to those who have touched them in any way.
The atheistic idea is so nonsensical that I do not see how I can put it in words.
Science is bound, by the everlasting vow of honour, to face fearlessly every problem which can be fairly presented to it.
I have not had a moment's peace or happiness in respect to electromagnetic theory since November 28, 1846. All this time I have been liable to fits of ether dipsomania, kept away at intervals only by rigorous abstention from thought on the subject.
Simplification of modes of proof is not merely an indication of advance in our knowledge of a subject, but is also the surest guarantee of readiness for farther progress.
Ether is the only substance we are confident of in dynamics.
One thing we are sure of and that is the reality and substantiality of the luminferous ether.
Let nobody be afraid of true freedom of thought.
Let us be free in thought and criticism; but, with freedom, we are bound to come to the conclusion that science is not antagonistic to religion, but a help to it.
I have no satisfaction in formulas unless I feel their numerical magnitude.
The vortex theory [of the atom] is only a dream.
Itself unproven, it can prove nothing, and any speculations founded upon it are mere dreams about dreams.
We only know God in His works, but we are forced by science to admit and to believe with absolute confidence in a Directive Power-in an influence other than physical, or dynamical, or electrical forces.
To live among friends is the primary essential of happiness.
At what time does the dissipation of energy begin?
Symmetrical equations are good in their place, but ' vector ' is a useless survival, or offshoot from quaternions, and has never been of the slightest use to any creature.
Scientific wealth tends to accumulate according to the law of compound interest.
Every addition to knowledge of the properties of matter supplies the physical scientist with new instrumental means for discovering and interpreting phenomena of nature, which in their turn afford foundations of fresh generalisations, bringing gains of permanent value into the great storehouse of natural philosophy.
Although mechanical energy is indestructible, there is a universal tendency to its dissipation, which produces throughout the system a gradual augmentation and diffusion of heat, cessation of motion and exhaustion of the potential energy of the material Universe
I have not the smallest molecule of faith in aerial navigation other than ballooning, or of the expectation of good results from any of the trials we heard of. So you will understand that I would not care to be a member of the Aeronautical Society.
There cannot be a greater mistake than that of looking superciliously upon practical applications of science. The life and soul of science is its practical application.
The fact that mathematics does such a good job of describing the Universe is a mystery that we don't understand. And a debt that we will probably never be able to repay.
Nothing can be more fatal to progress than a too confident reliance on mathematical symbols; for the student is only too apt to take the easier course, and consider the formula not the fact as the physical reality.
I can never satisfy myself until I can make a mechanical model of a thing.
If I can make a mechanical model, I can understand it. As long as I cannot make a mechanical model all the way through I cannot understand.
We all confidently believe that there are at present, and have been from time immemorial, many worlds of life besides our own. . . . [This] may seem wild, and visionary; all I maintain is that it is not unscientific.
If we can't express what we know in the form of numbers, we really don't know much about it.
Mathematics is the only true metaphysics.
If you study science deep enough and long enough, it will force you to believe in God.
When you cannot measure, your knowledge is meager and unsatisfactory.
If you cannot measure it, then it is not science.
I believe that the more thoroughly science is studied, the further does it take us from anything comparable to atheism.
To measure is to know.
When you are face to face with a difficulty, you are up against a discovery.
There is nothing in science which teaches the origin of anything at all.
[Of the ether] it is no greater mystery at all events than the shoemakers' wax.
[Referring to Fourier's mathematical theory of the conduction of heat] .
.. Fourier's great mathematical poem.