Astell alleges a specific provocation for it: she had just been reading the duchess's memoirs, a case-study of a bad marriage, in which both sides were to blame.
Perry, Ruth. The Celebrated Mary Astell: An Early English Feminist. University of Chicago Press.
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Her book reached a fourth edition...
Author summary
Mary Astell
Best known as a feminist theorist and polemicist, MA
is also a fine poet and an energetic and funny controversialist on the political affairs of the late seventeenth and early eighteenth century. A High Anglican...