The Importance of Sentiment in Promoting Reasonableness in Children explores the contributions that eighteenth-century Scottish philosophers Thomas Reid, Adam Smith, and David Hume make to our understanding of important factors in the development of children as they gradually acquire central features of reasonableness. Smith and Reid explicitly discuss the importance of sentiment and reason in the development of children. Their views are favorably influenced by the writings of their English predecessor Joseph Butler. Hume, too, valued much of Butler’s thinking. But, unlike Smith and Reid, he said little about Butler’s specific reflections on sentiment and reason. Despite this, one of the aims of this little book is to show that each contributes to our understanding today of what the encouragement of the philosophical thinking of children can play in helping them to come to an appreciation of reasonableness. They advocate a social environment for children that moves them to mix sentiment and reason in ways that support the values of reasonableness.