A Quote by Percy Williams Bridgman on certainty and determination

To find the length of an object, we have to perform certain physical operations. The concept of length is therefore fixed when the operations by which length is measured are fixed that is, the concept of length involves as much as and nothing more than the set of operations by which length is determined.

Percy Bridgman (1882 - 1961)

Source: The Logic of Modern Physics, 1927

Contributed by: Zaady