Could it be a sort of saying or idiom to explain this sentence?
"Just because he was ugly, it didnít make him dumb."
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.
I thought about "dumb - unable to speak"...
You are, of course, correct that the main definition of "dumb" is "unable to speak". However, it is frequently used to mean "stupid" and because there is a well-known (although entirely incorrect) connection between [lack of] beauty and [lack of] intelligence, my interpretation seemed much more likely. I've never across someone who thinks that someone is stupid because they can't speak.