How did Academic skepticism challenge Stoicism and Epicureanism?

Academic skepticism, which emerged within Plato's Academy during the 3rd century BCE, challenged the prevailing dogmatic schools of Stoicism and Epicureanism by questioning their fundamental epistemological claims.1

Led by philosophers such as Arcesilaus and Carneades, the Academic skeptics argued that it is impossible to establish a definitive criterion for distinguishing between true and false knowledge. While Stoics and Epicureans believed they had identified reliable standards for truth, the Academics countered that no such absolute certainty could be attained.1

Instead of claiming that knowledge is impossible, they proposed a "limited, or probabilistic, skepticism." They argued that because absolute truth is inaccessible, individuals should rely on reasonable or probable standards to guide their judgments and actions. By denying the possibility of certain knowledge, they sought to undermine the dogmatic confidence of their contemporaries, shifting the focus from absolute certainty to the practical application of probability.1