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; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be.


Lecture on "Electrical Units of Measurement" (3 May 1883), published in Popular Lectures Vol. I, p. 73

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William Thomson Quotes

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...

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...

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...

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...