sure, but these words have precise definitions. Paul alluded to this when he wrote "in fact, it would not be a bad definition of math to call it the study of terms that have precise meanings".
"Ratio", "Square Root", and "Integer" have precise definitions, whereas "self interest" is imprecise.
Define 'precise'. :P
http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_the...
Not without words you can't.