I'm thinking of somebody who cannot empathize with or understand the actions of many other people, someone who would immediately rule other people out as not credible, trustworthy or worthy of their time, without really taking the time to know them. There are probably other, more precise definitions for being "small." I'll look into it.
A little later he wrote: I think closed-minded or narrow-minded is what I meant.
small-minded
/smɔːlˈmʌɪndɪd/
adjective
having or showing rigid opinions or a narrow outlook; petty.
Element 99 