Hearn was educated at Portora Royal School in Enniskillen, Ireland and later studied at Trinity College Dublin from 1842.
[citation needed] Hearn's teaching career began in 1849, when he was selected as a professor of Ancient Greek at the Queen's College, Galway, which had been established a few years earlier.
[2] In January 1859, Hearn stood as a candidate for the Parliament of Victoria, in a by-election for a seat in the Victorian Legislative Assembly, he was embarrassingly unsuccessful.
In 1874 and 1877 he again stood unsuccessfully for parliament, evading the ban on professors running for election on the basis that as a dean, he had lost his professorial title.
Plutology, or the Theory of the Efforts to Satisfy Human Wants,[3][4] a political economy textbook which was well regarded by economists such as William Stanley Jevons and Francis Ysidro Edgeworth, although there is some indication that Hearn's book was derived from that of several less well known English writers.
[1] Hearn's last major project was an attempt to codify Victorian law, which resulted in a book published on its theoretical basis, The Theory of Legal Duties and Rights,[6] and a draft bill which ultimately entered parliament for consideration.
"[1] Although the codification was not adopted, Hearn nevertheless helped through his other work to establish a strong and dominant tradition of positivism in Australia.