In his superb book Enough!, Vanguard founder Jack Bogle at one point quotes pollster Daniel Yankelovich:
“The first step is to measure what can easily be measured.
This is okay as far as it goes.
The second step is to disregard that which cannot be measured, or give it an arbitrary quantitative value. This is artificial and misleading.
The third step is to presume that what cannot be measured is not very important.
This is blindness.
The fourth step is to say that what cannot be measured does not really exist.
This is suicide.”