phil 100 review - sfu.cakathleea/phil100/lectures/100.08.review.pdf · 1. swimming five times a...

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PHIL 100 Review

Induction versus Deduction

Example

1. All dogs have tails.2. Jack is a dog.Therefore, Jack has a tail

Is this an inductive or valid deductive?Why?

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1. If Jack is dog, then Jack dislikes cats.2. Jack doesn’t dislike cats,Therefore Jack is not a dog.

Inductive or valid deductive?

Why?



Why?

But are premises true?

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Why?

But are premises true?

So, this argument is_________ but not ________.

1. If Jack is a dog, then Jack is a member of the species canuslupus.

2. Jack is a member of the species canus lupus.3. Therefore Jack is a dog.

Is this a valid argument?

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1. If Jack is a dog, then Jack is a member of the species canuslupus.

2. Jack is a member of the species canus lupus.3. Therefore Jack is a dog.

Is this a valid argument?

1. If Jack is a dog, then he is a mammal.2. Jack is a mammal.3. Therefore, Jack is a dog.

1. Yesterday, I saw seven black crows.2. Today, I saw nineteen black crows.3. Therefore all crows are black.

Inductive or deductive?

Why?

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Angus Polls completed a survey showing that 97% of all Canadians donot want an election in the next six weeks.

The poll was balanced for age, gender, ethnic background, socio-economic class & party allegiance.

_____________________Therefore 97% of all Canadians do not want an election in the next six

weeks.

Is this an inductive or a deductive argument?

Why?

What is the traditional problem of induction?

Why can we not justify induction by pointing out that, in fact, ouruniverse is an orderly one, governed by the laws of physics, etc.?

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Necessary and sufficient conditions.

A necessary condition. If X is a necessary condition for Y then….?


A necessary condition. If X is a necessary condition of Y then isimpossible to have Y without X.

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A necessary condition. If X is a necessary condition of Y then isimpossible to have Y without X.

E.g. Having four sides is necessary for being a square. Being unmarried is a necessary condition of being a bachelor. Being composed of H2O is necessary for being water.

Sufficient conditions. If X is a sufficient condition for Y, then….

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Sufficient conditions. If X is a sufficient condition for Y, then thepresence of X guarantees the presence of Y. (I.e. you couldn’thave X without also having Y.)

E.g.1. Swimming five times a week is a sufficient condition for being

physically fit.2. Having a gym “GO pass” is a sufficient condition for admittance to

the gym.3. Being on the official voter’s list and showing a valid driver’s license

for being able to vote in Canada.

Necessary or Sufficient?

1. Is being female a necessary or a sufficient condition for being pregnant?

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1. Is being female a necessary or a sufficient condition for being pregnant?Necessary. Fortunately, it is not sufficient!


1. Is being female a necessary or a sufficient condition for being pregnant?2. Is being a good person a sufficient condition for having a happy life?

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1. Is being female a necessary or a sufficient condition for being pregnant?2. Is being a good person a sufficient condition for having a happy life? No. Good people sometimes have unhappy lives.


1. Is being female a necessary or a sufficient condition for being pregnant?2. Is being a good person a sufficient condition for having a happy life?3. Is having TB antibodies a necessary or a sufficient condition for having

contracted TB?

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contracted TB?Both necessary and sufficient.



contracted TB?4. Is being a bachelor necessary for being unmarried?

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contracted TB?4. Is being a bachelor necessary for being unmarried?

NO. You could be a widower.

Positions in Philosophy of Mind.

A. Cartesian DualismThere are two substances, mind and body, which are essentially

distinct—which have different essences or necessary properties.

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Positions in Philosophy of Mind.

A. Cartesian DualismThere are two substances, mind and body, which are essentially

distinct—which have different essences (necessary and sufficient)properties.

Something could not be a body unless it had extension (occupies space);everything with extension is a body.

Something could not be a mind unless it had thought; everything that hasthoughts is a mind.

What two famous problems follow from this view?

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Problem of other minds. If the only mind we have access to is our ownminds, then the only knowledge we can have about other minds is aboutother people’s behavior.


Problem of other minds. If the only mind we have access to is our ownminds, then the only knowledge we can have about other minds is aboutother people’s behavior.

We can infer that what is going on in other people’s minds is what goes onin our minds in similar circumstances.

What kind of argument is this? Inductive or deductive?

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Problem of other minds. If the only mind we have access to is our own minds, thenthe only knowledge we can have about other minds is about other people’s behavior.

We can infer that what is going on in other people’s minds is what goes on in ourminds in similar circumstances.


Is it a good argument?


Problem of other minds. If the only mind we have access to is our own minds, thenthe only knowledge we can have about other minds is about other people’s behavior.

We can infer that what is going on in other people’s minds is what goes on in ourminds in similar circumstances.


Is it a good argument? Induction based on a single case, my own case. Not a goodinductive argument.

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B. The Mind/Body Problem. If the mind and body are suchradically different kinds of substances, how do they interact?Indeed, WHERE do they interact if the mind is not located in space.

Behaviorism

There is no problem of other minds: Except under exceptionalcircumstances, we do not have any trouble understanding whatpeople are thinking.

There is no mind/body problem: When we talk about other people’smental or psychological states, we are NOT referring to some innerghostly event to which only the other person has access.

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BEHAVIORISM: The terms in our language that we use to talk aboutother people’s mental states refer dispositions to behave in a certainway in certain circumstances —patterns of behavior— or what theperson would do if he or she was under certain circumstances.

Example.

Thinking that it is about to rain = if the person were to go outside, he orshe would take a raincoat or umbrella AND if s/he were outside, heor she would glance up at the sky AND if s/he were driving and thecar windows were open, then s/he would close the windows AND..

So, according to behaviorism…

The mind is NOT private; it is possible for me to know your behavioraldispositions better than you do.

There is no problem of mind/body interaction because all of our language termsthat refer to mental states refer to behavioural dispositions, not about somesort of inner ghostly states.

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The Identity Theory

The Mind and the Body are one and the same thing. That is, everyparticular thought or psychological state, P, is a particular brainstate, B.

Someday when our knowledge of brain science grows large enough,we will be able to identify each thought with a particular kind of brainstate, although of course, we cannot do that at the present.

The Identity Theory

The Mind and the Body are one and the same thing. That is, everyparticular thought or psychological state, P, is a particular brainstate, B.

Someday when our knowledge of brain science grows large enough,we will be able to identify each thought with a particular kind of brainstate, although of course, we cannot do that at the present.

The Identity Theory is a MONIST view: there is only one kind ofsubstance or stuff in the world and that is body, or matter, orphysical stuff.

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According to the Identity theory….

How do we solve the problem of other minds? At present, given thecurrent state of brain science we have to rely on other people’sbehavior to understand what they are thinking. But in the future,when we have access to their brain states, we will be able toobserve their thoughts.

How do we solve the mind/body problem?

According to the Identity theory….

How do we solve the problem of other minds? At present, given thecurrent state of brain science we have to rely on other people’sbehavior to understand what they are thinking. But in the future,when we have access to their brain states, we will be able toobserve their thoughts.

How do we solve the mind/body problem? There is no mind/bodyproblem. They are one and the same thing.

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Functionalism

There are two routes to functional theories:

1. Largely from biology, using the notion of functional role, or the differencebetween a role and its occupier.

On this view, we can define certain kinds of entities in terms of what they do (asopposed to what they are made out of). E.g. a can opener, the GovernorGeneral of Canada.

A mental state of a particular kind is defined in terms of what causes it to come about(external stimuli, other mental states) and what it causes (other mental states,behaviors)—in terms of its relations to inputs, outputs and other mental states.

1. From computer science, using the notion of a machine state.

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2. From computer science in terms of a machine state.

If we a Turing Machine Table for human psychology, then each psychological statewould be identical to a specifc machine state from that—to column within aTuring Table.

Each column in a Machine Table says what the machine will do for any of thepossible inputs that could occur next.

As the machine changes state, what it would do, given any of the possible inputs,changes—I.e. each machine state defines a unique set of behaviors given anyparticular input.

E.g. If you are already irritated when someone steps accidentally on your foot, youwill respond somewhat rudely. But if you are in a very happy mood, and arecontemplating your glorious future, you will react far more generously whensomeone accidentally steps on your foot. Different internal states = differentresponse to the same stimulus.

What does functionalism say about the two problems?First, functionalism is neither a physicalist nor a dualist view: whatever fillsthe right functional role/machine state IS a mental state of a particularkind.

Theoretically, many different kinds of things could have minds, as long asthey have the correct kind of functional states.

If we find that people have brain states that can be identified with thestates of the machine table for human psychology, then we can say thatOUR mental states are realized by physical brain states.

Thus, our thoughts would not be be private; we could both predict themfrom the machine table AND someday we might be able to “see” themwith the right sort of neurophysiological tools.

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Eliminativism

Eliminativism: The view that there are certain aspects of the mind aboutwhich we are radically mistaken.

Or to put this another way: the kinds of psychological/functional statesthat we assume people MUST have, such as ordinary beliefs anddesires, just do not exist.

Because our understanding of ourselves to date has been basedprimarily on our access to our own conscious states and to our ownand other people’s behavior…

It could turn out that we have access to very little of our own cognitiveactivity.

It could turn out that the access we have to our own mental states isquite faulty. If our access to the external world is as bad as Gilbertsays it is, why do we think that our access to our inner world—whichis equally complicated—is not equally problematic?

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