[NTG-context] Example markup

[Vyatcheslav Yatskovsky]

Hello,

There are examples (usually one paragraph long) in my lecture text, and 
I want them to be typeset in smaller font (\tfx). An excerpt:


The entities in question fall into two broad categories: {\em 
endogenous} (intrinsic to the SUI itself) and {\em exogenous} (belonging 
to a system's environment).

\example{All processes that take place inside Earth (and other planets) 
are considered endogenous. These processes make the continents migrate, 
push the mountains up, trigger earthquakes and volcanism, and are driven 
by the warmth that is produced in the core of Earth.}


More text...



I hesitate about how to define \example. I know about \definedescription 
and \defineenumeration, but they seem not much logically suitable to me. 
What could you advise?


Regards,
Vyatcheslav