Abstract: Reading the Seventeenth and Eighteenth Centuries critical texts about French classical tragedies shows us how the tragic genre used to be assessed and what the values attributed to it were. In those texts personal and subjective taste has either very little or no place at all: they build up the illusion of an entirely objective assessment. This rationalism comes with the attempt to consider the qualities of tragedies. Those qualities extend beyond the aesthetic field: tragedies rank at the highest in the genre’s hierarchy because they are thought to be endowed with moral values. This assumed ethical worth led the Eighteenth Century playwrights to emphasise moral standards in their plays and, according to the Twentieth Century critics, this is the very fact that paradoxically entailed the loss of aesthetic values in tragedies during the Age of the Enlightenment.