What?

I am as loud as thunder ;  yet
as  a quiet as a whisper
I am a god to some ; yet
to others I am a devil.
 

I am a hero but also a killer
I am a freedom fighter but also a terrorist
 

To  one eye  I am solid yet
to another  I am as liquid
I am all light  and also all dark
 

To one man I am all knowing
to another  a I am a fool
I am matter but also at
the same time anti-matter.
 

So what am I ?