"I know more than I can express in words, and the little I can express

would not have been expressed, had I not known more."

There seems to be something the matter with this sentence.  There seems

to be some break down in grammatical or logical thought. Or else I

simply don't understand. 

Could someone re-state this sentence in other words so that I can

understand it? It's the second "not" that throws me. Does he know more,

or doesn't he? If he had not known more, would he  have expressed it or

not?

I tried changing the order to 

"Had I not known more than I can express in words, the little I can

express would not have been expressed." 

This seems marginally more comprehensible, but I'm still baffled. Is he

saying that if he knew less than he does he would have expressed it?

Help!