Functionalism

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Feb 23, 2014 (3 years and 6 months ago)

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Functionalism








Albert Parker

May 3, 2001

Two Camps

Dualist

“Mind

is

formal

and

abstract”




Substance



two

radically

different

kinds

of

substances

in

the

universe
:

material

objects

and

immaterial

minds

(Descartes)


Property

-

two

radically

different

kinds

of

properties

in

the

universe
:

material

properties

(like

weight)

and

immaterial

properties

(like

pain)

Materialist

“Mind

is

the

wet

and

slimy

stuff

in

our

heads”




Behaviorism



mind

reduces

behavior

or

dispositions

to

behavior


Physicalism



mental

states

are

brain

states


Functionalism



mental

states

are

defined

by

causal

relations


Strong

AI



minds

are

programs

implemented

in

computers







(Searle MLS, p46
-
7 and SA 31)


How do we observe the mind?

Dualist’s

Problem
:

Metaphysical

Gap

The

mind

can

be

observed

through

introspection
.

It

is

just

the

minds

of

others

that

cannot

be

observed
.

Materialist’s

Problem
:

Leibniz

Gap

“It

must

be

confessed,

moreover,

that

perception,

and

that

which

depends

on

it,

are

inexplicable

by

mechanical

causes,

that

is,

by

figures

and

motions
.

And

supposing

that

there

were

a

mechanism

so

constructed

as

to

think,

feel

and

have

perception,

we

might

enter

into

it

as

into

a

mill
.

And

this

granted,

we

should

find

only

on

visiting

it,

pieces

which

push

one

against

another,

but

never

anything

by

which

to

explain

a

perception
.

This

must

be

sought

in

the

simple

substance,

and

not

in

the

composite

or

in

the

machine”

(CMB,

Cummins

4
)


Analysis

of

consciousness

bogged

down

for

lack

of

analytical

tools!


(Psychology

crippled

and

behaviorism

was

spawned

by

taking

the

mind

out

of

psychology)

(
6
-
7
)

What to do?

For

the

materialist,

Functionalism

provides

a

bridge

over

the

Leibniz

gap
:

Mental

states

are

defined

in

terms

of

their

abstract

causal

roles

within

the

wider

information

processing

system
.

A

given

mental

state

is

characterized

in

terms

of

its

abstract

causal

relations

to

environmental

input,

to

other

internal

states

and

to

output

(Churchland,

NP,

351
)
.



Example 1:
Pump
is a functional kind, being implemented by hearts, propellor and case,
vibrator and one
-
way valve, centrifuges, piston and sleeve arrangements
(MBC, Cummmins 7).

Example 2:
Mouse Trap
is a functional kind, being implemented by spring traps, cage
traps, a sack of grain attached to a trip wire, a cat or specially bred killer rat

Example 3:
Being in
pain

is a state carried out characterized by its causal relations to:



behavior
: wincing and crying out



external input
: skin being burned



other internal states
: the desire to make the pain go away and belief of what will bring

relief.


Functional kinds are specified by their roles and


not by the material in which they are instantiated.
(Churchland, NP, 351).


How does Functionalism Deal
with the Leibniz Gap?


Functionalism:
mental concepts are revealed through function
not in terms of intrinsic features. That is, deal with function, to heck
with the form.


Leibniz Gap
occurs because function can’t be read from form


Hence, Functionalism is a bridge over the Gap.


“…trying to understand perception by studying only neurons is like trying
to understand bird flight by studying only feathers”
(Marr 27)


“…
once we have explained the causal basis of consciousness in terms of
the firing of neurons … in the various cortical layers, it seems we still
have a phenomenon left over”

(Searle MLS, p55)



Emile Durkheim
created the
functional orientation

by codifing
the distinction of structure and function in the social sciences. He
published his functional analysis in a number of empirical studies:


The Division of Labor in Society (1893)


The Elementary Forms of Religious Life (1912)


Durkheim recognized the potential problems of functionalism that
critics like John Searle and Patricia Churchland still espouse today in
reaction to neurophilosophical functionalism:




To discover the
need

that a structure
functions

to meet does
not
necessarily reveal its
cause
-

the sequence of events that created the structure in the first place. To assume it
does puts the cart before the horse. (Turner 17)



J. Dewey
The Reflex Arc Concept in Psychology

(1896) is the
“opening shot” of Functionalism in Psychology

(Bergmann 678).


H. Putnam

“Minds and Machines” in
Dimensions of the Mind
(1960) was the first to argue that
minds

are things that we can
conceive

solely

in terms of input, output, and various functional
relations.

(Hardcastle 2
-
3)

Whose Idea was this?

Some Functionalist
Achievements


von

Neumann

architecture

(
1943
-
1957
)



Still

used

in

today’s

desk
-
tops,

lap
-
tops,

calculators

and

palm

pilots

that

grace

every

office

and

half

the

homes

in

America

(von

Neumann

xii)



Barlow’s

First

Dogma

(
1972
)

“A

description

of

that

activity

of

a

single

nerve

cell

which

is

transmitted

to

and

influences

other

nerve

cells

and

of

a

nerve

cell’s

response

to

such

influences

from

other

cells,

is

a

complete

enough

description

for

a

functional

understanding

of

the

nervous

system”

(Barlow

380
)



Theory

of

the

Cellebar

Cortex

(
1969
)

This

“regular


cortical

structure

is

interpreted

as

a

simple

but

powerful

memorizing


device

for

learning

motor

skills”

(Marr

14
)


… something was going wrong

“I

was

myself

caught

up

in

this

excitement

(of

the

60
’s)
.

Truth,

I

also

believed,

was

basically

neutral,

and

the

central

aim

of

all

research

was

a

thorough

functional

analysis

of

the

structure

of

the

central

nervous

system



the

way

seemed

clear



but

somewhere

underneath,

something

was

going

wrong



the

cerebellar

study



suggested

that

one

could

hope

to

understand

cortical

structure

in

functional

terms



but

at

the

same

time



it

did

not

much

enlighten

one

about

the

motor

system

-

it

did

not,

for

example,

tell

one

how

to

go

about

programming

a

mechanical

arm”

(Marr

14
-
15
)



“Functionalism

looks

nice

on

paper

to

those

who

know

nothing

about

how

brains

work
.


(Freeman

115
)
.



“Functionalism



is

merely

the

last

gasp

of

classical

psychology
.


(Bergmann

678
)




The

functionalist

strategem

is

a

smoke

screen

for

the

preservation

of

error

and

confusion



It

needs

to

be

revealed

for

the

shortsighted

and

reactionary

position

it

is
.


(MBC,

Churchland

506
-
7
)


“If you are tempted to functionalism, I believe you do not need refutation,
you need help.”

(Searle, TRM, 9)




What’s wrong with Functionalism?


ABSURDITIES

CAN BE DEFENDED


for example, alchemy, in
the face of elemental chemistry, can be defended using the
functionalist stratagem, thusly:



Ensouled

in

mercury”

or

“sulphur”

is

an

abstract

functional

state
.

“Mercury,”

for

example,

actually

refers

to

the

disposition

to

reflect

light,to

liquefy

under

heat,

to

unite

with

other

matter,

etc
.

(
these

are

functional

kinds)
.

It

is

the

total

syndrome

of

occurent

and

causal

properties

of

a

metal

or

substance

that

matters,

not

the

corpuscularian

details

of

the

substrate

(
function

matters,

not

the

implementation)
.

Alchemy,

it

is

concluded,

comprehends

a

level

of

organization

in

reality

that

is

distinct

from,

and

irreducible

to,

the

organization

found

at

the

level

of

corpuscularian

chemistry
.

(MBC

Churchland

507
)
.





NEED DETAILS!

-

the success of implementing
Neural Networks

illustrates that an elementary understanding of brain microstructure
funds a fertile conception of what cognition really is.
(MBC Churchland 198)



QUALIA

can not be reduced to something else
, because if you
could they would be something else, and they are not something else.
(Searle, RM 51)


Let’s Patch This Up!


Oceans of Ink have been spilled in the debate over functionalism

…”

(Hasker 29)



Valerie Hardcastle: “Functionalism is neither very strong nor very
controversial.”



Jaegwon Kim: global reductionism is not possible, but some local
reductions are: “qualia are intrinsic properties if anything is, and to
functionalize them is to eliminate them as intrinsic properties.”

(Hardcastle 29).



Elliot Sober: “Functionalism got off on the wrong foot. The problem is
that
function

is ambiguous … ”

(97)



New Paradigm or Paradigm Shift
?


John Searle:
“Most of the recently fashioned materialist concepts of the mind


such
as behaviorism, functionalism and physicalism


end up denying that there are any such
things as minds as we ordinarily think of them …
Now, why do they do that?
(MBS
15).

(We need to stop using) the antique and obsolete vocabulary of “mental” and
“physical”, “mind” and “body”
(MLS 47).

Any satisfactory account of the mind must take
into account:
consciousness, intentionality, subjectivity,
and
mental
causation”
(MBS 17).


Reactions: “
Many of them, especially the younger


generation, agree with me, but I am amazed at the


number and vehemence of the defenders”
(SA 29)



David Marr: “
Almost never can a complex system of any


kind be understood as a simple extrapolation from the


properties of the individual components … (there are three)


levels at which an information processing device must be understood
(24
-
5)
:


Computational
Theory

What

is

goal

of

computation

and

logic

of

the

strategy?

Representation and
algorithm

What

is

representation

of

the

input

and

output

and

the

algorithm

map?

Hardware
Implementation

How are the representation
and the algorithm realized
physically?

My Take


Cummins

states

that

if

a

theory

is

any

good,

it

must

be

explanative

in

and

of

itself
.

Some

functionalist

defenses

to

attacks

sound

like

the

non
-
intuitive

“hook
-
hook”

argument

illustrated

on

page

3

of

MBC

handout
.



Functionalism has problems in its
pure

form (
everything

is function,
defined in terms of inputs and outputs). NOTE: The
new
paradigms
presented here (at least Marr’s) have functionalist components.



Searle’s paradigm may be a new one. Marr’s is a shift.

References


H. B. Barlow. “Single snits and sensation: a neural doctrine for perceptual psycology?”
Perception 1.


G. Bergmann. “The Contribution of John B. Watson.” J. M. Scher editor.
Theories of the Mind.
The
Free Press. New York, 1962.


P. S. Churchland.
Neurophilosophy.
The MIT Press. Cambridge, 1986.


R. Cummins and D. D. Cummins.
Minds Brains and Computers: The Foundations of Cognitive
Science
. Blackwell Publishers. Malden, MA, 2000.


W. J. Freeman and C. A. Skarda. “Mind/Brain Science: Neuroscience on Philosophy of Mind.” E.
Lepore and R. V. Gulick editors.
John Searle and His Critics.
Basil Blackwell. Cambridge, 1991.


V. Hardcastle.
How to Build a Theory in Cognitive Science.
State University of New York Press.
New York, 1996.


W. Hasker.
The Emergent Self.
Cornell University Press. Ithaca, 1999.


D. Marr.
Vision
. W.H. Freeman and Company. New York, 1982.


J. von Neumann.
The Computer and the Brain
. Yale University Press. New Haven, 2000.


J. Searle. “Is the Brain’s Mind a Computer Program?”.
Scientific American
. Jan 1990, p 118.


J. Searle.
Minds, Brains and Science.
Harvard University Press. Cambridge, 1984.


J. Searle.
Mind, Language, and Society.
Basic Books. New York, 1998.


J. Searle.
Rediscovery of the Mind..
The MIT Press. Cambridge, 1992.


E. Sober. “Putting the Function Back into Functionalism.” W. G. Lycan editor.
Mind and Cognition
.
Basil Blackwell. Cambridge, 1990.


J. H. Turner and A. Maryanski.
Functionalism
. The Benjamin/Cummings Publishing Company.
Menlo Park, CA, 1979.