guided by practical experience and observation rather than theory; "a hardheaded appraisal of our position"; "a hard-nosed labor leader"; "completely practical in his approach to business"; "not ideology but pragmatic politics"
unreasonably rigid in the face of argument or entreaty or attack
stubbornly unyielding; "dogged persistence"; "dour determination"; "the most vocal and pertinacious of all the critics"; "a mind not gifted to discover truth but tenacious to hold it"- T.S.Eliot; "men tenacious of opinion"