This is an ironic twist since fire captains have to burn books. Beatty says that this is just a part of the job that comes with years of burning books. He needs to understand what exactly he is dealing with. The knowledge a person might have in a certain situation when completing a book burning could lead to some shady dealing so Beatty maintains his knowledge. Beatty's answer isn't very straight-forward or believable in the first chapter. This is why Montag makes some startling revelations after Beatty is burned in chapter 3.
Here is something Beatty says about knowledge that I think demonstrates his character:
You always dread the unfamiliar. Surely you remember the boy in your own school class who was exceptionally 'bright,' did most of the reciting and answering while the others sat like so many leaden idols, hating him.
I think Beatty is talking about himself right here. He was that intelligent boy. He speaks as if he supports the burning, but I wonder if he is just wiser. He knows better than to go against an entire society gone mad.
so whats the answer? i really dont understand what you mean by that. somee Miss575! :(