This paper focuses on the English philosopher Mary Astell’s marginalia in Lady Mary Wortley Montagu’s personal copy of the 1704 edition of Pierre Bayle’s Pensées diverses sur le comète (first published in 1682). I argue that Astell’s annotations provide good reasons for thinking that Bayle is biased toward atheism in this work. Recent scholars maintain that Bayle can be interpreted as an Academic Sceptic: as someone who honestly and impartially follows a dialectical method of argument in order to obtain the (...) goal of intellectual integrity. In her commentary, however, Astell suggests that: (i) if Bayle were honest and impartial in his inquiries, then he would not have pretended to attack popular superstition, only to undermine generally-held religious beliefs; and (ii) if Bayle valued intellectual integrity, then his argument for a society of virtuous atheists would not have relied upon a deceptive equivocation in terms. I conclude that the rediscovery of this marginalia is valuable for enhancing our appreciation of Astell as an astute reader of one of her most enigmatic contemporaries. (shrink)