in 58 and 57 B.C. his political career, except for a brief period just
before his death, was over, and it is at this time that his period of great
literary activity begins, In 55 he produced the work _De Oratore_, in 54
the _De Re Publica_, and in 52 the _De Legibus_, all three works, according
to ancient ideas, entitled to rank as philosophical.[5]

From 51 to 46 B.C., owing first to his absence in Cilicia, then to the
civil troubles, Cicero almost ceased to write. But in the latter year he
was reconciled with Caesar, and as the Senate and law courts were closed
against him on his refusal to compromise his political principles, he
betook himself with greater devotion than ever to literature. The first
work written in 46 was the _Hortensius_, or _De Philosophia_, now lost. It
was founded on a lost dialogue of Aristotle, and set forth the advantages
of studying Philosophy. During the same year Cicero completed several
oratorical works, the _Partitiones Oratoriae_, the _Brutus_, or _De Claris
Oratoribus_, and the _Orator_, all of which are extant.

Early in 45 Cicero lost his beloved daughter Tullia. He passed the whole
year in retirement, trying to soothe his grief by incessant writing. In
quick succession appeared

_De Consolatione_, an attempt to apply philosophy to the mitigation of his
own sorrow and that of others;

_Academica_, an exposition of the New Academic Philosophy, advocating
probability rather than certainty as the foundation of philosophy;

_De Finibus Bonorum et Malorum_, a work criticising the most prominent
views entertained concerning Ethics;