Committing to moral principles can be a good strategy if a sufficient number of other people in your social environment share these principles: it will reduce your transaction costs in social cooperation. Commitment adds a recognition sign to the paradigmatic Tit-for-Tat model in game theory: if you can commit to cooperate, others will incur less risk in cooperating with you, and everybody will be better off. (Robert Axelrod’s 1984 book The Evolution of Cooperation, which developed a simple model without the possibility of communication, generated a voluminous literature). In other words, if you are virtuous and enough others in your environment are too, virtue signaling is a good strategy. If others know that you are in the habit of honesty and decency, your life will be easier.

With respect to a free society, committing to principles of reciprocity among natural equals (to use James Buchanan’s terms) will also contribute to maintaining or developing that society. This is a major idea in Buchanan’s Why I, Too, Am Not a Conservative; I think it is approximately translatable in Hayekian terms. This small book by Buchanan is a good and non-technical introduction to his ethical theory but (trigger warning!) you may be challenged.

The idea of committing to moral principles even has implications for the conduct of war. Trying to occupy the high moral ground in wartime may not lead the enemy to compete for the top of the barrel: after all, if your group is waging a just war, moral principles are probably not the enemy’s strong point. However, the moral principles that political leaders signal may help keep some human decency in their soldiers, which will be useful after demobilization. Furthermore, this strategy will certainly economize on the capital of support from other people with moral principles in the world. (Buchanan and Hayek were probably less radical than the ideas I am expressing in matters of war, but I would be surprised if they wouldn’t have agreed with this paragraph.)