Hi Clive, thanks for the answers.
"I employ the term 'dogmatist' in the sense in which S. uses dogmatikos, namely, to designate one who makes positive or negative assertions about the nature of things, on the basis of what one considers to be evidence and reasoned arguments and doctrines."
This may work, but I'm not completely sure that it's clear enough. In any case "he" and "they" may be used to refer to someone whose gender is not known. But I know there are people who dislike both usages.
Do you feel you need the comma after 'things'? Perhaps a comma after 'evidence' rather than 'and'?
Yes, I should remove that comma. Regarding "and", the point is that "reasoned" goes with both "arguments" and "doctrines."
Is the term 'dogmatist' compatible with one who is influenced by doctrines?
Yes, in its technical usage.
Cheers, Sextus