William Edward Hartpole Lecky opens his historical and philosophical study by examining the foundational conflict between two rival systems of ethics: the inductive utilitarianism that bases morality on experience and self-interest, and the intuitive school that asserts a natural, innate perception of duty and moral obligation. He explores how these theoretical positions manifest in human behaviour and historical progress.
The author investigates the moral condition of the pagan empire, reviewing the philosophies of the Stoics, the Epicureans, and the Egyptians. He demonstrates how these intellectual expressions reflected the underlying material and social state of society, tracing their influence on legislation and literature while diagnosing the deep-seated corruption that baffled emperors and philosophers alike.
A central theme of the work is the transition from ancient pagan morality to the triumph of the Christian religion in Europe. Lecky treats the Church not through the lens of theology, but simply as a moral agent, examining its transformation under prosperity, asceticism, and barbarian invasions. He details the growing sense of the sanctity of human life, the history of charity, the moral influence of monasteries, and the changing position of women.
The text continues with an exhaustive analysis of the association of ideas, the genesis of conscience, and the distinction between the higher and lower parts of human nature. Lecky argues that while utilitarianism reduces morality to a calculation of pleasure and pain, the intuitive system alone preserves the uncorrupted conception of pure disinterestedness and self-sacrifice.
Throughout the work, the author demonstrates that while the fundamental principles of morality remain constant, the practical standards and the prominence assigned to specific virtues alter predictably with civilisation. He concludes that the progress of mankind depends not on the pursuit of happiness, but on the allegiance to an intrinsic moral law that elevates human nature towards the divine.