The absence of romance in my history will, I fear, detract somewhat from its interest; but if it be judged useful by those inquirers who desire an exact knowledge of the past as an aid to the interpretation of the future, which in the course of human things must resemble if it does not reflect it, I shall be content. In fine, I have written my work, not as an essay which is to win the applause of the moment, but as a possession for all time.
Thucydides explains that his purpose is not primarily to entertain but to provide an accurate account that can help later readers understand human affairs. He accepts that a history without romantic or dramatic embellishment may be less immediately attractive, but argues that careful knowledge of past events has a more enduring value.
The passage also reflects his belief that recurring features of human behaviour allow the past to illuminate the future. He does not claim that events will repeat exactly, but suggests that similar circumstances can produce comparable patterns of conflict, ambition, fear and political calculation.
His description of the work as a “possession for all time” contrasts lasting usefulness with short-lived applause. The quotation therefore expresses both a principle of historical inquiry and a view of authorship: evidence, accuracy and explanatory value should take priority over immediate popularity.