“When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science”. Lord Kelvin
"Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it”. Samuel Johnson