He sat on the Committee of the National Society for Women's Suffrage and his wife, Caroline Anna Croom Robertson was a college administrator.

[2] In 1864 he was appointed to help William Duguid Geddes with his Greek classes, but he devoted his vacations to working on philosophy.

He remained there until he was forced by ill-health to resign a few months before his death, lecturing on logic, deductive and inductive, systematic psychology and ethics.

A comprehensive work on Hobbes was never completed, though part of the materials were used for an article in the Encyclopædia Britannica, and another portion was published as one of Blackwood's "Philosophical Classics."

He and his wife, the college administrator Caroline Anna Croom Robertson, were involved in social work;[4] he sat on the Committee of the National Society for Women's Suffrage, and was actively associated with its president, John Stuart Mill.