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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 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.

Lord Kelvin#1

ScienceMeasurementDataKnowledge

About this quote

What does it mean?
Measuring and quantifying knowledge is essential to move from vague ideas to true science.
In plain terms
If you can't measure it, you don't truly understand it yet.
What can you take from it?
Use numbers to test and deepen your knowledge.

Where it applies

  • scientific research
  • business metrics
  • self improvement

Putting it to work

  • define metrics
  • track progress numerically

Questions to consider

  • What can't be measured but matters?
  • How do numbers change understanding?

Another view

Some valuable things like ethics or beauty resist strict quantification.

More from Lord Kelvin

  1. There cannot be a greater mistake than that of looking superciliously upon the practical applications of science. The life and soul of science is its practical…

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  2. 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 …

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  3. Heavier-than-air flying machines are impossible.

    Permalink to quote #4

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