Joanna Baillie (1762–1851) was renowned in the earlier nineteenth century as a playwright. This paper argues that the kind of drama she produced was distinctly philosophical, both in its content, examining the danger of the passions in human life, and its educational aims, showing how the characters’ failures to regulate their passions brought about their downfall, which served as a warning to the audience. After exploring why Baillie used drama as her philosophical medium, the paper considers the major criticisms of her from Francis Jeffrey, the first editor of the Edinburgh Review. The paper defends Baillie against his criticisms.