A series of thirty epistolary essays offers compact reflections on customs, aesthetics, language, and moral psychology. Topics range from the force of habit, wealth, card-playing and duelling, to languages, painting, musical expression, punctuation, reading practices, and the English tongue; other letters examine Homeric heroism, Shakespeare, handwriting, the analogy among arts, and errors of association. Each letter combines philosophical observation, cultural criticism, and practical examples to question received opinions and encourage independent judgment.