I have been thinking about belief and whether it is under the control of the will. This question is important since it lies at the foundation of the very possibility of an 'ethics of belief.' People believe all sorts of things, and it is quite natural to suppose that some of the things they believe they are not entitled to believe, they have no right to believe, they are not justified in believing, they ought not believe. The characteristic beliefs of Holocaust deniers, for example, are not only demonstrably false, but also such that their holding by these nimrods is morally censurable. One has the strong sense that these people are flouting their epistemic duties.
But such predicates are applicable only if beliefs and cognate attitudes are under voluntary control. The point could be put as follows: Epistemic deontology is a viable project only if doxastic involuntarism is false.
I am coming to the view that doxastic involuntarism is false (thereby joining the excellent company of Augustine, Aquinas, Descartes and other great philosophers) and that at least some beliefs are under voluntary control. But of course the logically prior question is: What is belief? Whether belief is under voluntary control depends on what belief is.
One cannot understand belief except in relation to other mental states. So let's consider how believing and knowing are related. They are obviously different, and yet they share a common element. Suppose we say that what is common to S's knowing that p and S's believing that p is S's acceptance of p. I cannot (occurrently) believe that Oswald acted alone unless I accept the proposition that Oswald acted alone, and I cannot (occurrently) know that he acted alone with accepting the very same proposition. To accept, of course, is to accept-as-true. It is equally obvious that what is accepted-as-true might not be true. Those who accept that the earth is flat accept-as-true what is false. Now one could analyze 'S knows that p' as follows:
a) S unconditionally accepts-as-true p
b) p is true
c) S is justified in accepting-as-true p.
This is modelled on, but diverges from, the standard justified-true-belief (JTB) analysis of 'know' the locus classicus of which is Plato's Theaetetus.
And one could perhaps analyze 'S believes that p' as follows:
a) S unconditionally accepts-as-true p
d) S does not know that p.
These analyses accommodate the fact that there is something common to believing and knowing, but without identifying this common factor as belief. The common factor is acceptance. A reason for not identifying the common element as belief is that, in ordinary language, knowledge excludes belief. Thus if I ask you whether you believe that p, you might respond, 'I don't believe it, I know it!' Do I believe the sun is shining? No, I know the sun is shining. Do I know that I will be alive tomorrow? No, but I believe it. That is, I give my firm intellectual assent to the proposition despite its not being evident to me. Roughly, belief is firm intellectual assent in the absence of compelling evidence.
Surely this is what we mean by belief in those cases that clearly count as belief. Lenny the liberal, for example, believes that anthropogenic global warming is taking place and is a dire environmental threat. Lenny doesn't know these two putative facts; he believes them: he unconditionally accepts, he firmly assents to, the two propositions in the absence of compelling evidence. And it seems clear that an element of will is involved in our boy's belief since the evidence does not compel his intellectual assent. He decides to believe what he believes. His believing is in the control of his will. This does not mean that he can believe anything he wants to believe. It means that a 'voluntative surplus' must be superadded to his evidence to bring about the formation of his belief. Without the voluntative superaddition, he would simply sit staring at his evidence, so to speak. There would be no belief and no impetus to action. Beliefs typically spill over into actions. But there would not be even a potential 'spill over' unless there were a decision on Lenny's part to go beyond his evidence by superadding to it his firm intellectual assent.
"But aren't you just using 'believes' in an idiosyncratic way?" It is arguably the other way around. Someone who says he believes that the sun is shining when he sees that it is shining is using 'believes' in an idiosyncratic way.
"But then isn't this just a terminological quibble? You want to substitute 'accepts' or 'accepts-as-true' for 'believes' in the standard JTB analysis of 'knows' and you want to reserve 'believes' for those cases in which there is unconditional acceptance but not knowledge." The question is not merely terminological. There is an occurrent mental state in which one accepts unconditionally propositions that are not evident. It doesn't matter whether we call this 'belief' or something else. But calling it 'belief' comports well with ordinary language.
Let me now elaborate upon this account of belief, or, if you insist, of Aquinian-Pieperian belief.
1. Belief is a form of acceptance or intellectual assent. To believe that p is to accept p, and to disbelieve that p is to reject p. One may also do neither by withholding p.
2. If acceptance is the genus, then knowing, believing, and supposing are species thereof. In knowing and believing the acceptance is unconditional whereas in supposing it is conditional. It follows that believing is not common to believing and knowing as on the JTB analysis. To think otherwise is to confuse the genus (acceptance) with one of its species (belief).
3. What distinguishes believing and knowing is that the believer qua believer does not know, and the knower qua knower does not believe. Both, however, accept. But here I must confess to a difficulty. What I just wrote appears objectionably circular. It seems to boil down to this: what distinguishes believing and knowing is that they are distinct!
If believing and knowing are species of the genus acceptance, what is the specific difference whereby the one is distinguished from the other? Believing that p and knowing that p are not distingusihed by the common propositional content, p. Nor are they distinguished by their both being modes of unconditional acceptance. Can we say that they differ in that the evidence is compelling in the case of knowing but less than compelling in the case of believing? That is true, but then the difference would seem to be one of degree and not of kind. But if knowing and believing are two species of the same genus, then we have a difference in kind. Perhaps the difference is that belief is based on another's testimony whereas knowledge is not.
4. It is essential to belief that it involve both a proposition (the content believed) and a person, the one whose testimony one trusts when one gains access to the truth via belief. To believe is to unconditionally accept a proposition on the basis of testimony. If so, then there are two reasons why it makes no sense to speak of perceptual beliefs. First, what I sense-perceive to be the case, I know to be the case, and therefore, by #3 above, I do not believe to be the case. Second, what I sense-perceive to be the case I know directly without need of testimony.
On this approach, the difference between believing and knowing is that believing is based on testimony whereas knowing is not. Suppose p is true and that my access to p's truth is via the testimony of a credible witness W. Then I have belief but not knowledge. W, we may assume, knows whereof he speaks. For example, he saw Jones stab Smith. W has knowledge but not belief.