Quantitative Methods -- Quote for thinkers

The original statement of the principle: "garbage in .... garbage out"

Mathematics may be compared to a mill of exquisite workmanship, which grinds you stuff of any degree of fineness; but nevertheless, what you get out depends on what you put in; and as the grandest mill in the world will not extract wheat-flour prom peascods, so pages of formula will not get a definite result out of loose data.

- Quarterly Journal of the Geological Society of London, Volume 25, 1869, Lord Kelvin, when speaking of the calculations of the age of the earth