This article analyses Valla’s historiographical stance in the light of his dialectical assumptions about possibility, verisimilitude, and truth. I argue that, at variance with most humanists, Valla believed that historical truth should satisfy the requirements of logical necessity, being therefore incompatible with verisimilar reconstructions of past events. However, Valla also realized that a critical method of assessment grounded in verisimilitude was indispensable to the analysis of doubtful accounts and traditions. In order to explore these matters, Valla developed a genre distinct (...) from history proper and closer to the forensic, inquisitorial tradition. While history had to deal with necessary truths, the aim of ‘historical inquisitio’ was to draw probable conclusions from pieces of conjectural evidence. According to Valla’s dialectical principles, these conclusions were not absolutely true but could be considered true thanks to the notion of intellectual acumen, which allowed Valla to take a leap from the field of possibility or verisimilitude to that of truth and necessity. (shrink)