This article explores the place of non-human animals in Catharine Macaulay’s understanding of moral education. Other Early Modern writers instructed parents and governors to discourage children from mistreating animals in order to prevent the development of cruelty or callousness, but said little else. Macaulay’s views run deeper. Focusing on her Letters on Education (1790), I show that Macaulay centers her view on the development of the natural capacity for sympathy, through which we discover the principle of equity, and thereby cultivate the crucial virtue of benevolence. I then show that Macaulay repeatedly connects sympathy and benevolence to the early associations formed through one’s relations to sentient creatures, revealing how her associationistic psychology grounds her views on morality and moral education.