Percentage Values without parent elements?

If an element has no parent (such as <BODY>) and it uses a relative 
size to specify something, what is the correct action?

My current course of action is to map the relative size from the 
assumed default size.  Such that specifying 
body { font-size: larger }
is the same as
body { font-size: large }


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| Neil St.Laurent  neil@bigpic.com
| Big Picture Multimedia