Rationality Through Reasoning

Rationality Through Reasoning John Broome

When someone believes she ought to F, often her belief causes her to intend to F. How does that happen? Call this ‘The motivation question’. Some philosophers think that a belief cannot cause an intention. This is one motivation for noncognitivism, which claims that a normative belief is not really a belief. My answer to the motivation question will be compatible with cognitivism, but it is not committed to any particular view about the metaphysics of normativity.

An initial answer: many people are disposed to intend to F when they believe they ought to F. This answer is correct but very thin. It is not entirely empty, because it locates the causal process within the person. The disposition must work through some causal process. I hope to show it sometimes works in a philosophically interesting way, through the person’s own action.

Some people – ‘sheep’ – have the disposition strongly. Others – ‘goats’ – do not. It is plausible that rationality requires you to intend to F when you believe you ought to F. So the sheep are rational and the goats are not. I am to show that people can improve their rationality in this respect, by reasoning. Reasoning is an activity by means of which we can improve our rationality. Goats can turn themselves into sheep.

Rationality is a source of requirements. Example: Rationality requires of you that you do not both believe p and believe not p.

Another requirement: Instrumental Requirement: Rationality requires of you that, if You intend e, and if You believe that m is a means implied by e, and if You believe that m is up to you yourself now, then You intend m.

Instrumental Requirement more formally. Rationality requires of N that, if N intends at t that e, and if N believes at t that, if m were not so, because of that e would not be so, and if N believes at t that, if she herself were not then to intend m, because of that m would not be so, then N intends at t that m.

Another: Enkrasia. Rationality requires of you that, if You believe that you yourself ought that p and if You believe that it is up to you yourself now whether or not p, then You intend that p.

You satisfy many requirements of rationality automatically. But you can also bring yourself to satisfy them by means of active reasoning. I hope to show that reasoning can bring you to satisfy enkrasia.

Reasoning is a process whereby some of your attitudes cause you to acquire a new attitude. Not every such process is reasoning, and even when it is reasoning, it might not be active reasoning – reasoning you do as opposed to a process that happens in you. What further conditions on the process are sufficient for it to be active reasoning?

To answer, I start with reasoning that concludes in a belief. Example of a process that could be active reasoning, if it satisfies other conditions : You wake up believing it is raining, because you hear dripping water. You have a standing belief that, if it is raining the snow will melt. As your pull your wits together, these two beliefs together cause you to acquire the belief that the snow will melt.

I assume active reasoning is conscious, because you are normally conscious of what you do. So: First condition for active reasoning. The attitudes you reason with are conscious. This means at least that you are conscious of the attitudes’ contents. For instance, you consciously believe it is raining.

One way you can come to be in a state of conscious belief is to call the content of the belief to mind. One way to do that is to express the content to yourself in inner speech. Example: you say to yourself ‘It is raining’.

In explicit reasoning you say to yourself the contents of the attitudes involved. Example: you say to yourself ‘It is raining. If it is raining, the snow will melt. So the snow will melt.’ I do not assume conscious reasoning is necessarily explicit. But is sometimes convenient to set it out in explicit form.

Second condition for active reasoning: Active reasoning is a rule-governed operation on the contents of your attitudes. The operation is algorithmic or computational. But note, it is an operation on the contents of attitudes, which are propositions, not sentences.

A rule may be described by a schema. Example, the modus ponens rule: From p and (If p then q) derive q’. (This is a simplified version of the modus ponens rule; more later.)

Now an example of active reasoning with attitudes other than beliefs. I concentrate on reasoning that concludes in an intention. Specifically, I concentrate on instrumental reasoning. Example: You intend to visit Venice, and you believe that you will not do so if you do buy a ticket. Your intention and belief together cause you to acquire the intention of buying a ticket.

This reasoning could be made explicit: ‘I shall visit Venice I shall not visit Venice if I do not buy a ticket. So I shall buy a ticket.’ The first and third sentences express intentions; the second expresses a belief. This is a plausible example of instrumental reasoning, but it is not correct. More later.

Definition: a marked content is a content marked at the content of a particular sort of attitude. Formally, it is a pair consisting of a proposition and the type of attitude it is. For instance: <I shall go to Venice; intention> (I treat the proposition as the whole content, so the mark is attached to the content rather than part of it)

Conditions for active reasoning. First. The attitudes you reason with are conscious. This means at least that you are conscious of their marked contents. You are conscious of the propositional content in a believing way or an intending way – as believed, or as intended. Second. Reasoning is a rule-governed operation on the marked contents of your attitudes.

A rule of reasoning is, for example: From <I shall F; intention> and <If I shall F, I shall G; belief> derive <I shall G; intention>. (NB for later. This rule is incorrect.)

The modus ponens rule should also be seen as a rule on marked contents. It is: From <p; belief> and <If p then q; belief> derive <q; belief>.

Mine is a first-order account of reasoning. It involves no normative second-order beliefs, such as the belief that you ought to believe the snow will melt , or the belief that you ought to intend to buy a ticket. You reason with the attitudes, not about the attitudes.

Next, when is reasoning correct? Reasoning is correct if and only if it follows a correct rule. A rule is correct if and only if it corresponds to a basing permission of rationality. A basing permission is the negation of a basing prohibition.

Examples of basing prohibitions: Do Not Affirm the Consequent. Rationality requires you not to believe q on the basis of believing p and believing that if q then p. No Belief From an Intention. Rationality requires you not to believe p on the basis of any set of attitudes that includes an intention.

Form of a basing prohibition: Rationality requires of N that it is not the case that N has attitude A at tA and N has attitude B at tB and N has attitude C at tC and … N has attitude K at tK and N’s attitude K at tK is based on N’s attitude A at tA and N’s attitude B at tB and N’s attitude C at tC and …

Notes: ‘Attitude’ includes non-attitudes, such as non-beliefs and non-intentions. A basing prohibition does not prohibit the attitudes themselves, only the basing of one on the others.

I cannot analyse ‘based on’. Some points: If Aat tAis based on B at tB, then Aat tAis caused by B at tB. (The converse is false in general.) The basing is inferential, not evidential. (Examples of evidential basing: You believe it will rain tomorrow on the basis of tonight’s red sky. You believe you will see kangaroos on the basis of your intention to visit Australia – this does not violate No Belief From an Intention.)

Form of a basing permission . Rationality permits N that N has attitude A at tA and N has attitude B at tB and N has attitude C at tC and … N has attitude K at tK and N’s attitude K at tK is based on N’s attitude A at tA and N’s attitude B at tB and N’s attitude C at tC and ….

For example: Modus Ponens Permission. Rationality permits you to believe q on the basis of believing p and believing that if p then q.

Instrumental Permission. Rationality permits you to intend that m on the basis of Intending that e Believing that m is a means implied by e, and Believing that m is up to you yourself. Note there is no ‘now’ in the last condition, whereas there is a ‘now’ in the corresponding condition of the Instrumental Requirement. More later.

Instrumental Permission more formally. Rationality permits N that: N intends at tA that e, and N believes at tB that m is a means implied by e, and N believes at tC that m is up to her herself, and N intends at tK that m, and N’s intention at tK that m is based on N’s intention at tA that e, and N’s belief at tB that m is a means implied by e, and N’s belief at tC that m is up to her herself.

The following rule corresponds to Instrumental Permission. From <e; intention> and <m is a means implied by e; belief> and <m is up to me; belief> derive <m; intention> This rule seems obviously correct.

Example of explicit reasoning that follows the correct instrumental rule: I shall visit Venice My buying a ticket is a means implied by my visiting Venice. My buying a ticket is up to me. So I shall buy a ticket. The example of instrumental reasoning I started with does not conform to this rule. It can be correct only if it is enthymematic, containing suppressed premises.

It seems obvious that reasoning is made correct by basing permissions of rationality, rather than by requirements of rationality. But what is the connection between basing permissions and requirements? Reasoning is a means by which you improve your rationality. For that, it must bring you to satisfy requirements of rationality, as indeed it does.

Difference between Instrumental Permission and Instrumental Requirement: You are required to intend the means only when you believe the means is up to you now. You are permitted to intend the means on the basis of intending the end and believing the means is up to you at any time. Reasoning can bring you to satisfy the requirement only if it takes place before the requirement bites.

So instrumental reasoning brings you to satisfy the instrumental requirement. That is its point. Yet it is made correct by the instrumental permission. The instrumental permission must be derived from the requirement in some way. I am not sure exactly how.

Enkratic Permision. Rationality permits you to intend that p on the basis of Believing that you yourself ought that p, and Believing that it is up to you yourself whether or not p. (Again, no ‘now’ in the last condition, whereas there is a ‘now’ in the requirement Enkrasia.)

Corresponding rule: From: <I ought that p; belief> and <It is up to me whether or not p; belief> derive <p; intention>

You can reason consciously, operating on the contents of your attitudes, following this rule. Indeed, your reasoning may be explicit. For instance: I ought to get some coffee. It is up to me whether or not I get some coffee. So I shall get some coffee. The last sentence expresses an intention.

This is active reasoning, which is something you do. It can bring you to satisfy the requirement of Enkrasia, and in that way increase your rationality. It answers the motivation question in a satisfactory way. You can motivate yourself to do what you believe you ought to do.

Rationality Through Reasoning