Life is very rigorously defined, however it's not unequivocal:

http://en.wikipedia.org/wiki/Life#Definitions

A word not having a rigorous definition means it cannot be discussed scientifically. Hence the actual problem of studying the existence of life, e.g. is a virus alive?

please note. Unequivocal and rigorous are synonyms.

http://www.thesaurus.com/browse/unequivocal/4

>A word not having a rigorous definition means it cannot be discussed scientifically.

Life is discussed scientifically in many contexts yet it is not unequivocally or rigorously defined. In fact there's an entire field based on the study of life. It's called biology, aka the study of life. If a scientific field can stem from a word that does not have a rigorous or unequivocal definition, then it can be discussed scientifically.

@dimino

I'm getting pretty tired too. You choose not to accept the facts even when a scientific description proving my point is thrown in your face. Ideas need evidence for support, you have presented me with ideas, but no evidence.

The folks in the field are in agreement with me, (see the old wikipedia link I sent you). You got nothing, only empty claims.

I'm getting tired of this conversation, so I'll just leave you with the idea that words carry different definitions in different contexts. There is no scientific context by which "race" is currently known. You can choose to accept that, or you can continue to deny that, it doesn't really matter to any of the folks who work in this field.