Lecture 7

Induction

What Is Induction?

• In deduction, we move from premises to conclusion. But where do the premises come from?

• One way is through analytic judgments, e.g., “All triangles are three-sided figures”.

• In an analytic judgment , the subject and predicate are logically connected.

Analytic Judgments and Austrian Economics

• Much of Austrian economics, as developed by Mises, consists of analytic judgments and deductions from them.

• Some example: Every action uses means to achieve ends

• An actor always chooses his most highly-valued end.

Learning From Experience

• Induction concerns truths that are not analytic judgments. These are learned from experience.

• How do we know, e.g., that people need to eat in order to live? This isn’t something that we deduce from the concept of “human beings” or “eating food.”

Why Induction Is a Problem

• Experience is always about particular events at a particular time. (This is a conceptual truth.) How can we get a universally true proposition from such experience?

• Suppose, e.g., that we have found on a number of occasions that waters runs downhill. What justifies the generalization, “Water always runs downhill?”

Joyce’s Answer to the Problem of Induction

• There isn’t a generally accepted answer to this problem.

• Joyce’s solution depends on the fact that the generalizations we make from experience are about causes. By “cause” he means the reason for something, i.e., what makes a thing to be what it is.

• Joyce’s approach is quite similar to the “new” approach to induction offered by Leonard Peikoff in David Harriman, The Logical Leap.

Joyce’s Answer Continued

• Sometimes we can recognize a causal relationship immediately. For example, I grasp immediately that I caused the previous slide to shift to this one.

• Sometimes it is very difficult to find out what the cause of something is. For example, there are all sorts of things that take place once I click the mouse that bring about the slide’s movement. You have to know a great deal to discover these.

Types of Cause

• Joyce takes an Aristotelian approach to causality.

• In this view, there are four types of cause: • Final • Formal • Material • Efficient

Final Cause

• The final cause of something is its purpose. • In the Aristotelian view, purposes aren’t

confined to human action. • This doesn’t mean everything has a mind.

Rather, everything has a natural end. For example, the purpose of the heart is to pump blood.

Formal and Material Causes

• The formal cause is the shape of something, Joyce gives the example of the shape of a statue.

• The material cause is what something is a made of. For example, the material cause of a marble statue is the marble that makes up the statue.

• The formal and material causes are called intrinsic causes. They make no reference to anything outside the thing whose causes they are.

Efficient Cause

• The efficient cause is the closest to the modern conception of cause. It is what brings about a change.

• In the example of changing the slides, I am the efficient cause, because I brought about the change from one slide to the next.

• In the Scholastic view, the efficient cause is a substance, not an event. This contrasts with the views of most modern philosophers.

More About Causes

• The final and efficient causes are called extrinsic causes because they refer to what is outside the object. For the final cause, this is the end, or aim, of the object. For the efficient cause, it is the substance that brings about a change in the object.

How Does Joyce Solve the Problem of Induction?

• We know what to look for when we are trying to discover the cause of something. Depending on the situation, it can be any of the four causes.

• But how does this help us solve the problem of induction? That is, how will it enable to come up with universal causal generalizations?

Abstraction

• When you arrive at a cause of something, you can abstract from the particular details of the instance you are considering.

• In the example of changing the slides, I can abstract from saying that clicking the mouse this time caused this slide to move. I can say, “clicking the mouse will cause a slide to move”, without referring to a particular occasion.

The Uniformity of Nature

• Even if you abstract from particular causal occasions, though, how does this solve the problem of induction? How do you know that the abstract causal statement will always apply?

• Joyce appeals to the principle of the uniformity of nature: the same cause will under the same circumstances produce the same effect.

• This principle, he claims, is a metaphysical principle that applies to the physical world.

A Mistake About the Uniformity Principle

• According to Joyce, this would be a wrong way to reason:

• Nature is uniform • On various occasions, my clicking the

mouse causes a slide to move • Clicking the mouse in the right

circumstances will always cause a slide to move.

What’s the Mistake?

• Once I say that my clicking the mouse causes the slide to move, i.e, then I have already appealed to uniformity. That is, I have claimed that it is in the nature of clicking the mouse in the appropriate circumstances that as a result a slide will move. I’m already relying on uniformity, so I don’t need to bring it in as the major premise of a syllogism.

The Inductive Syllogism

• This is different from ordinary induction. • In an inductive syllogism, if something applies to

all the logical parts of a whole, it is true of the whole.

• This is sometimes used in geometry. • The conclusion doesn’t establish a logical

connection between the nature of the whole subject and the property attributed to it. The property might apply to each of the parts in different ways.

Perfect and imperfect Induction

• This is another type of induction. In this type, you enumerate, i.e., list the instances in a certain whole that possess a certain property. You conclude that every instance has the property. Note the difference from the inductive syllogism, which is about logical parts---sub-types---of a whole, not instances.

Perfect and Imperfect Induction Continued

• If you enumerate every instance, the induction is called perfect and is valid. Suppose I ask each student in this class, “Are you interested in logic?” and everyone says yes. Then I can conclude everyone in the class is interested in logic.

• If I generalize from a few instances, the induction is imperfect and isn’t worth much.

Hume on Induction

• Joyce’s Scholastic account wouldn’t be accepted by most modern philosophers who work on induction.

• They have been influenced by a famous argument of David Hume

• Hume denied that the principle of the uniformity of nature could be established by reason. Induction rests on habit

Hume’s Argument

• Hume said that if the principle of uniformity could be rationally established, this would be either by reason or experience.

• It isn’t contradictory to deny uniformity. Thus, the principle isn’t a truth of reason.

• If we say experience supports it, because the same causes have been observed to have the same effects in the past, how does this justify an inference to the future? It can do so only if uniformity is already assumed.

Karl Popper’s Radical Approach

• Popper accepts Hume’s argument • His response is that we don’t need induction. We

don’t need to say that from the fact that a number of instances of a causal relation have been observed, we are justified in inferring a causal law.

• He says that we come up with a hypothesis that can be falsified. We don’t need anything more in science.

Objections to Popper

• On Popper’s view, we can say that a theory hasn’t yet been falsified, but this gives us no grounds to expect that it will continue to be true in future.

• This is a skeptical view. We don’t know, e.g., that stepping in front of a speeding car will have bad consequences for you if you do it.

Example of a Fallacy

• Christopher Weldy has sent in this case: • “Do you realize that anything which applies to the

government also applies to God. That the government is the one earthly entity that closest resembles God. If obeying to the government, if blind faith and blind obedience in the government is wrong, same thing goes for God.”

• He asks, Is this an example of Begging the Question?

What’s Wrong with the Argument?

• This isn’t strictly a case of begging the question, because the argument doesn’t start with the premise that not obeying the state is like not obeying God, and then conclude to this same proposition.

• But it assumes a controversial premise—the state is like God---that only those who already reject disobedience are likely to accept.

Another Example

• One person wondered whether the argument we have just discussed has an undistributed middle term. I don’t think so.

• This example is also from Christopher: • “You see the word obedience appear a lot in the

Bible and you see Christians use the word obedience a lot. The last time a charismatic person used the word “obey” and “obedience” as often as the Christians do, a second world war erupted. I say, let’s get rid of both, the government and Christianity and all other religions for all I care.”

The Fallacy Exposed

• As Michael Ronnall suggests, this argument commits a post hoc, ergo propter hoc fallacy.

• The last time a charismatic person used the word “obey” and “obedience” as often as the Christians do, a second world war erupted

• Just because the war came after the use of “obedience”, it doesn’t follow that using this word caused the war.