Master of Arts in Pure and Applied Mathematics with honors, University St. Andrews, Scotland, 1958. Bachelor of Philosophy, University St. Andrews, Scotland, 1961.
Assistant in philosophy Queen's College, Dundee, Scotland, 1962-1963. Lecturer in philosophy University Dundee, 1963-1973, senior lecturer, 1973-1978. Regius professor of logic University Aberdeen, Scotland, since 1979.
Married Mary Elizabeth Ranson, August 19, 1959 (deceased 1984). Children: Margaret Anne, Catherine Mary, Ian Charles. Married Barbara Elizabeth Moncur, June 25, 1987.