Reread this sentence from the passage. with what scorn a pilot was looked upon, in the old times, if he ever ventured to deal in that feeble phrase, "i think," instead of the vigorous one, "i know! " how does twain organize the text to explain what he means?

I know what he means. It means somebody saying I think, isn't as easy as saying I know because you may be afraid to just go for it and be vigorous saying I know because you may be wrong, while I think can be any percentage of a chance of being right from 1% to 99%, while I know can either be 0% or 100% correct, so I could see why someone would say I think.