During the next few years the literary activity of Cicero suffered a check. The course of politics at Rome filled him with profound disappointment and disgust. Public issues, it became more and more plain, waited for their determination, not on the senate-house or the forum, but on the sword. The shameful collapse of his defence of Milo in 52 B.C. must have stung a vanity even as well-hardened as Cicero's to the quick; and his only important abstract work of this period, the _De Legibus_, seems to have been undertaken with little heart and carried out without either research or enthusiasm. His proconsulate in Cilicia in 51 and 50 B.C. was occupied with the tedious details of administration and petty warfare; six months after his return the Civil war broke out, and, until permitted to return to Rome by Caesar in the autumn of 47 B.C., he was practically an exile, away from his beloved Rome and his more beloved library, hating and despising the ignorant incompetence of his colleagues, and looking forward with almost equal terror to the conclusive triumph of his own or the opposite party. When at last he returned, his mind was still agitated and unsettled. The Pompeian party held Africa and Spain with large armies; their open threats that all who had come to terms with Caesar would be proscribed as public enemies were not calculated to restore Cicero's confidence. The decisive battle of Thapsus put an end to this uncertainty; and meanwhile Cicero had resumed work on his _De Legibus_, and had once more returned to the study of oratory in one of the most interesting of his writings, the _Brutus de claris Oratoribus_, in which he gives a vivid and masterly sketch of the history of Roman oratory down to his own time, filled with historical matter and admirable sketches of character. The spring of 45 B.C. brought with it two events of momentous importance to Cicero: the final collapse of the armed opposition to Caesar at the battle of Munda, and the loss, by the death of his daughter Tullia, of the one deep affection of his inner life. Henceforth it seemed as if politics had ceased to exist, even had he the heart to interest himself in them. He fell back more completely than ever upon philosophy; and the year that followed (45-44 B.C.) is, in mere quantity of literary production, as well as in the abiding effect on the world of letters of the work he then produced, the _annus mirabilis_ of his life. Two at least of the works of this year, the _De Gloria_ and the _De Virtutibus_, have perished, though the former survived long enough to be read by Petrarch; but there remain extant (besides one or two other pieces of slighter importance) the _De Finibus_, the _Academics_, the _Tusculans_, the _De Natura Deorum_, the _De Divinatione_, the _De Fato_, the _De Officiis_, and the two exquisite essays _De Senectute_ and _De Amicitia_.