自從孔子（551-479 B. C.）稱讚晉之董狐為良史之後，司馬遷（135-86C.）、班固（32-92）、陳壽（233-297）以降，多有人被稱為具良史之才，之後，且有不少人士談論良史的品質與特色。清中葉的章學誠（1738-1801）及民初的梁啟超（1873-1929）也談良史，到底良史的具體標準是什麼？這些標準又是誰定的？經過兩千多年，良史的定義有無變化，而其變化的原因何在？
本文想就良史在各時代所代表的意義加以分析討論，旨在說明「良史」的標準有其變與常，常的是其基本的無懼真誠，而變的則恰恰呈現該時代及人物的文化特色與歷史意識。

Since Confucius praised Dong Hu (董狐) of Jin as a Liang Shi (True Historian), the Grand Historian Sima Qian (司馬遷, 135-86 B.C.), Ban Gu (班固, 32-92), Chen Shou (陳壽, 233-297) have been also referred to have the quality of Liang Shi. Later, more and more people discussed about the characteristic features and nature of this designation. This issue had been raised again during the mid-Qing by the famous historical philosopher Zhang Xuecheng (章學誠, 1738-1801) and later by Liang Qichao (梁啟超, 1873-1929) in the early 20th Century. What were the criteria worthy of the title True Historian? And who according to what principles made these criteria? Throughout the last two thousand years, had the criteria of Liang Shi changed over time? And if it did, then what were the causes behind these changes? This article tries to discuss the meaning of
the Liang Shi in different periods respectively, indicating that there had been change and continuity regarding the criteria of being a True Historian. What remains constant is basically the fearlessness and honesty. The changing part, however, reflected the different cultural climates and historical consciousness of the people of the time.