Ethics of belief

The ethics of belief refers to a cluster of related issues that focus on standards of rational belief, intellectual excellence, and conscientious belief-formation. Among the questions addressed in the field are:
Origins of the debate: Clifford vs. James.
Contemporary discussions of the ethics of belief stem largely from a famous nineteenth-century exchange between the British mathematician and philosopher W. K. Clifford and the American philosopher William James. In 1877 Clifford published an article titled "The Ethics of Belief" in a journal called "Contemporary Review". There Clifford argued for a strict form of evidentialism that he summed up in a famous dictum: "It is wrong always, everywhere, and for anyone to believe anything on insufficient evidence." As Clifford saw it, people have intellectual as well as moral duties, and both are extremely demanding. People who base their beliefs on wishful thinking, self-interest, blind faith, or other such unreliable grounds are not merely intellectually slovenly; they are immoral. Such bad intellectual habits harm both themselves and society. We sin grievously against our moral and intellectual duty when we form beliefs on insufficient evidence, or ignore or dismiss evidence that is relevant to our beliefs.
Clifford's article provoked a spirited reply from the Harvard philosopher and psychologist William James. In his 1896 essay "The Will to Believe," James argued that there are times when it is permissible, or even obligatory, to form a belief even though we lack sufficient evidence for it. One sort of example he cites is "precursive faith," when belief runs ahead of the evidence but is essential for success (e.g., borderline-excessive self-confidence in an athlete). James made clear that he was not endorsing wishful thinking. He set forth strict conditions for when it was OK to believe without intellectually adequate evidence. Specifically, James laid down that (1) there must be no compelling evidence one way or another (i.e., the issue is "intellectually undecidable"), (2) both options must be "live hypotheses" for the relevant chooser (i.e., the chooser could sincerely believe either option), (3) the choice must be "forced" in the sense that one of the two options must definitely be chosen, and refusing to choose is tantamount to making one of the two choices, and (4) the choice must be "momentous" (i.e., deeply important or significant to the chooser). Famously, James argued that for many people the decision whether or not to believe in God satisfies these four conditions. Such people, James claims, have both an intellectual and a moral right to believe in God, even though by their own admission they lack sufficient evidence to justify this choice.
Earlier work on the ethics of belief.
Many thinkers before Clifford and James had important things to say about the ethics of belief. In ancient Greece, Socrates stressed the importance of self-examination, the pursuit of wisdom, and admitting how little one knows. Ancient skeptics such as Pyrrho, Arcesilaus, and Sextus Empiricus argued that we should suspend judgment on most controversial matters because powerful and perhaps equally compelling arguments can always be given on both sides. In modern times, René Descartes wrote extensively on norms of intellectual inquiry in his "Discourse on Method" (1637), as did John Locke in Book 4 of his "Essay Concerning Human Understanding" (1690). Three important thinkers—Blaise Pascal, Immanuel Kant, and Søren Kierkegaard—anticipated James in rejecting evidentialism and arguing that there are important matters on which, for practical or existential grounds, we should believe even if we lack sufficient evidence.
Epistemic norms.
Rules or standards that properly govern responsible belief-formation and the pursuit of intellectual excellence are what philosophers call epistemic (or "doxastic") norms. Widely accepted epistemic norms include: