Muiris ... had worked as a poet as well as a seanchaidh (historian/chronicler), composing poems in praise of Sir Lucas Dillon and his wife, on Brian Mac Diarmada (d. 1636) and Aodh Ó Conchobhair (d. 1632).
It is possible, though not proven, that he was the son of the Torna mac Eoluis Uí Mhaoil Chonaire, whose influence Ó Cléirigh acknowledged in print in 1643.
Such a genealogical link would provide the context for Muiris's ownership of a vellum manuscript containing a text of Naoimhsenchus naomh Insi Fáil used as an exemplar by Mícheál Ó Cléirigh in April 1636.
That is an indication that Muiris had a successful scholarly career and is a reminder that his relatively minor role in the AFM project should not be interpreted as implying that his scholarship was in any way inferior to that of the others of the 'Four Masters' team.
(Cunningham, p. 262) This is confirmed by a note written by Sir James Ware about 1636, when he recorded that he received the vellum fragment of annals he knew as Annales Prioratus Insulae Omnium SS in Loghree (now Bodleian MS Rawlinson B 488, folios 29–34) from Muiris mac Torna in August 1627 (dono dedit Mauritius Conry 27 Augusti 1627.)