The English writer Mary Wollstonecraft (1759 - 1797) is best known for her early feminist treatise A Vindication of the Rights of Woman, published in 1792. Two years earlier, Wollstonecraft published A Vindication of the Rights of Man (are you sensing a theme here?), which argued for republicanism and against the aristocracy. It's from this work that the above quote is pulled.
One important note: Mary Wollstonecraft is not to be confused with her daughter, Mary Wollstonecraft Shelley, the author of Frankenstein.
"No man chooses evil because it is evil; he only mistakes it for happiness, the good he seeks."
-Mary Wollstonecraft, from A Vindication of the Rights of Men (1790)
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