Sidgwick, Henry (1838–1900)

DOI: 10.4324/9780415249126-DC073-1
Version: v1,  Published online: 1998
Retrieved May 19, 2024, from

3. The dualism of practical reason

Sidgwick’s philosophical intuitionism houses a number of presumptively compatible, abstract, self-evident truths: a universalizability principle, a principle of rational prudence to the effect that, ceteris paribus, one should be equally concerned with all temporal parts of one’s life, and the principle of rational benevolence, the basis for utilitarianism (somewhat questionably derived by enjoining aiming at good generally and taking the good of each as equally important). He anticipates many recent utilitarians in interpreting the universalizability principle, derived from Kant, as purely formal, meaning simply that whatever ‘is right for me must be right for all persons in similar circumstances’ and therefore as compatible with utilitarianism (see Impartiality). However, such concordances notwithstanding, the conflict between the methods of utilitarianism and egoism, unlike that between intuitional morality and utilitarianism, is real. In an essay on The Methods, he explains that along with

(a) a fundamental moral conviction that I ought to sacrifice my own happiness, if by so doing I can increase the happiness of others to a greater extent than I diminish my own, I find also (b) a conviction – which it would be paradoxical to call ‘moral’, but which is none the less fundamental – that it would be irrational to sacrifice any portion of my own happiness unless the sacrifice is to be somehow at some time compensated by an equivalent addition to my own happiness.

(‘Some Fundamental Ethical Controversies’ 1889: 483)

Each of these convictions has as much clearness and certainty ‘as the process of introspective reflection can give’ as well as a preponderant, if implicit, assent ‘in the common sense of mankind’.

Excepting the criterion of mutual consistency, both convictions could pass the most demanding tests for self-evident truths: careful reflection, clarity and precision, and consensus among competent judges.Sidgwick therefore regards this as a ‘fundamental contradiction in our apparent intuitions of what is Reasonable in conduct’ and concludes, in the first edition of The Methods, that unless a way be found to reconcile ‘the Individual with the Universal Reason’, the ‘Cosmos of Duty is thus really reduced to a Chaos: and the prolonged effort of the human intellect to frame a perfect ideal of rational conduct is seen to have been foredoomed to inevitable failure’.

Whether Sidgwick regarded egoism as a matter of ethics or simply of rationality is hardly to the point; for him, the problem was to frame a rational way to live. He would have been dismayed to learn that the consistent (agent-relative) egoist would still challenge moral theorists at the close of the twentieth century.

In later editions and works, Sidgwick downplayed this dilemma, but his journal and letters reveal that he was always troubled by it. He had turned to ethics hoping to establish it as independently rational, perhaps a show of God’s order; his inquiry drove him to the conclusion that ethics was incoherent unless the utilitarian could infer ‘the existence of Divine sanctions’ that would ‘suffice to make it always every one’s interest to promote universal happiness to the best of his knowledge’. Evidence for the personal survival of death might help, but by 1887 he was concluding ‘that we have not, and are never likely to have, empirical evidence of the existence of the individual after death’. In a singular revelation, he explained that

When I was writing my book on Ethics, I was inclined to hold with Kant that we must postulate the continued existence of the soul, in order to effect that harmony of Duty with Happiness which seemed to me indispensable to rational moral life. At any rate I thought I might provisionally postulate it, while setting out on the serious search for empirical evidence. If I decide that this search is a failure, shall I finally and decisively make this postulate? Can I consistently with my whole view of truth and the method of its attainment?

(Henry Sidgwick, A Memoir 1906: 467)

His crisis of faith had proved enduring.

Citing this article:
Schultz, Bart. The dualism of practical reason. Sidgwick, Henry (1838–1900), 1998, doi:10.4324/9780415249126-DC073-1. Routledge Encyclopedia of Philosophy, Taylor and Francis,
Copyright © 1998-2024 Routledge.

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