Nick Fletcher PH317

How successful is Stich in arguing against the folk psychological category of

belief?

Folk psychologists interpret the term ‘because’ in any sentence describing

the relation between a belief and action literally; they believe that a belief is a

direct cause of an action. To construe a belief as a direct cause is to suggest that

one specific event is caused by, or has as a cause, one specific state. In order for

this to be true such singular causal statements require some kind of law that

relates the cause and the event. Thus, to say that a subject holds a belief that p

that causes the subject to act in a certain way in event e can only be true due to

underlying laws that specify nomological relations between beliefs and actions.

Folk psychologists believe that these laws are found in a ‘folk’ theory of mind

implicit in all our everyday talk about mental states. However, in positing this folk

psychologists simply invoke the concept of belief as an explanatory factor. It is

clear that it is not enough for a theory simply to invoke concepts as its laws as

this can be done completely arbitrarily; the laws a theory invokes must be

grounded somewhere in order to have validity. Supporters of folk psychology

argue that it is possible to invoke beliefs as explanatory factors because the laws

that govern the theory are grounded in the ordinary conception of belief. This

essay shall focus upon Stich’s argument in his 1978 article ‘Autonomous

psychology and the belief-desire thesis’ that he believes shows this intuitive

grounding to be false in many cases.

Stich’s argument begins from a single intuitive premise about beliefs. It

takes the form of a sufficient condition for the non-identity of belief properties; ‘if

an instantiation of belief property p1 differs in truth value from an instantiation of

belief property p2 then p1 and p2 are different properties’ (1978; pp.4), a premise I

shall refer to as the ‘non-identity premise’. This premise comes from the idea

that if one subject has a belief that is true and another has a belief that is false

they cannot be the same belief. Stich argues from this that if it can be shown that

two states that are instantiations of the same property yet differ in truth-value

they cannot be beliefs as we ordinarily conceive of them. If this is correct then

folk psychologists are unable to argue that invoking the concept of belief

according to our ordinary conception of the term is able to explain the link

between psychological properties and action.

Stich’s next move is to introduce what he calls the ‘principle of

psychological autonomy’ (1978; pp.1). To illustrate this principle, Stich uses a

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Nick Fletcher PH317

science fiction example in which there is technology available that can replicate a

human being exactly, ‘atom for atom’ (1978; pp.1). The original and the replica

human being will have identical psychological properties; for example amongst

other things they will have exactly the same beliefs, personality, memories and

tendencies as each other. As Stich puts it, ‘any psychological property

instantiated by one of these subjects will be instantiated by the other’ (1978;

pp.1). Stich adds to this that the organisms do not have to exist in the same time

or place, and that the replication may be accidental as these factors have no

effect upon whether or not the subjects are psychologically identical. Sitch also

assumes, and there are few that would disagree1, that mental and physical

properties are nomologically correlated. Instances of psychological autonomy can

occur in any of a number of ways, but the point of this example is to illustrate

exactly what is meant by ‘psychologically identical’.

It could be argued that the subject and the replica described above are not

psychologically identical as Stich suggests; whilst the replica will have memory

traces that exactly match the memories of the original, these will be merely

traces: he or she will not have the actual memories. For example, the replica may

have a memory trace of a childhood game he or she used to play, but will not

have an actual memory of the game; the replica did not exist at the time and so

could not have actually played the game. The original organism actually played

the game during childhood and so will have an actual memory of the game.

However, Stich has a ready answer for this concern, he posits that such

psychological properties are ‘hybrid’ in nature, and are analysable into purely

psychological properties and non-psychological properties (1978; pp.2). For

example he suggests that ‘remembering that p’ and ‘knowing that p’ can be

reduced to psychological properties ‘seeming to remember that p’ and ‘believing

that p,’ along with non-psychological properties such as ‘p being true’ or ‘the

memory trace being caused in a certain way by the fact that p’ (1978, pp.2).

Furthermore, Stich points out that intuitively only the purely psychological part of

the hybrid properties can be used to explain behaviour (1978; pp2); seeming to

remember that p will have the same effect upon behaviour whether or not the

organism actually has a real memory that p; equally, believing that p will have

the same effect upon behaviour as knowing that p. Thus, the principle of

psychological autonomy holds up to this concern as it only needs to take into

account properties that can be used to explain behaviour.

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Nick Fletcher PH317

In his article Stich next attempts to use the principle of psychological

autonomy and the non-identity premise to show that there are many belief

properties that cannot play the role they do in folk psychological theory. He does

this through four examples, each one of which is designed to describe a case in

which two subjects instantiate identical explanatory psychological properties, and

yet have different beliefs. If successful, this would show that

the belief properties of each pair of subjects cannot be explanatory psychological

properties, and the category of belief in folk psychology must be false.

1Only those who ascribe to the more extreme forms of dualism would disagree.

Firstly, Stich argues that self-referential beliefs cannot play any role in

explanatory psychological theory (1978; pp.5). I believe that I have successfully

completed a first year studying at Heythrop university, and if anyone were to ask

me if had I done this, I would reply that I had. However, if a replica of me was

asked the same thing, he would also reply that he had, even though he was only

created moments ago and thus in reality has not. In both cases it is clear that a

folk psychologist would argue that the both my belief and my replica’s belief that

we had completed a first year are among the causes of our replies. However,

according to Stich this cannot be the case, as the non-identity premise dictates

the truth-value of our beliefs are different so the belief property my replica

instantiates must be different to the belief property that I instantiate.

Furthermore, as we are replicas we must share all our explanatory psychological

properties according to the autonomy principle, and so our beliefs cannot be the

cause of our replies.

Secondly, Stich attempts to show that our beliefs about spatial and

temporal location cannot be used in explanatory psychological theory (1978;

pp.6). He describes a situation in which he has been cryogenically frozen,

transported to Iceland and defrosted after a couple of centuries. It is clear that

immediately after defrosting he will be psychologically identical to how he was

immediately before being frozen. However, Stich argues, both immediately

before and after being frozen he would believe that ‘it was the 20th century and

that there are many strawberry farms nearby’ (pp.6). As the truth-value of these

two statements is different, they cannot be instantiations of the same belief

property and thus could not explain why Stich might go looking for 20th century

strawberries either now or in the future. However, as future Stich is

psychologically identical to past Stich they must both instantiate the same

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Nick Fletcher PH317

explanatory psychological properties, which suggests that these explanatory

properties cannot be beliefs.

Next Stich attempts to show that beliefs about other people cannot be

used in explanatory psychological theory (1978; pp.6). He hypothesises that

somewhere in the universe exists a planet almost identical to ours in every

respect, but that in that other world Kripke was born in what the inhabitants of

that world call ‘South Dakota,’ whilst in our world he was born the state we call

Nebraska. However, Stichs doppelganger in the other world, who also gives

lectures on Kripke like the Stich in our world, teaches that he was born in the

state they refer to as ‘Nebraska’. In our world, Stich’s belief is correct, whereas in

the other world, the doppelganger’s belief is incorrect. Again Stich argues that as

the beliefs differ in truth-value the beliefs the two lecturers express in their

lectures are different, but as they are doppelgangers they must instantiate the

same explanatory psychological properties as one another under the principle of

autonomy. Thus their beliefs cannot be used to explain why they both teach that

Kripke was born in Nebraska.

Finally, Stich argues that beliefs about natural kind predicates cannot be

used in explanatory psychological theory (1978; pp.6). Using the example of

doppelganger planets once again, Stich hypothesises the existence of a plant

identical to our own but instead of water being H2O, their equivalent of water

takes the form XYZ. In our world during the 1700s someone is told by what he

believes to be a reliable source that lizards dissolve in water. This is clearly not

the case, but in the other world the same event occurs and it transpires that in

their world there are in fact lizards that dissolve in water. A folk psychologist

would argue the actions of the two doppelgangers of dipping lizards in water will

have been caused by the beliefs they acquire after hearing about this

phenomena from their sources, but similarly to the other examples, as the truth-

value of their beliefs differ but their explanatory psychological properties must be

the same, their beliefs cannot be used in explanatory theory.

Thus, Stich believes that he has shown that there are many categories of

belief that cannot be used in explanatory theory, and as such that folk

psychology is at best full of holes and at worst completely incorrect. However, I

believe that it is clear that Stichs argument is fatally flawed. Primarily, whether or

not someone’s beliefs are true or not has no effect on their behaviour as to them

their beliefs are always true. If they no longer believed them the original beliefs

would be replaced with new beliefs that the old beliefs were false. Therefore as

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Nick Fletcher PH317

the truth-value of our beliefs has no effect upon our actions, surely one cannot

appeal to truth-values in order to disprove the fact that a persons beliefs can act

as a cause of their action.

More importantly, the truth-value is not a property inherent to the belief

itself, it is decided by external factors. Whilst it is true that it is not possible that

two people can hold the same belief but with different truth-values, this is not

because truth-values have an effect upon beliefs; it is simply because a single

belief cannot be true and false at the same time. Thus the very premise from

which Stichs argument comes from is all but irrelevant to his argument. Indeed,

Stich’s examples are cleverly designed to create a situation in which two people

hold the same beliefs and perform the same actions, with only the truth-value of

the beliefs being different. In each, it is intuitively obvious that the belief is what

causes the action, but Stich postulates that this intuition is incorrect because ‘if a

particular belief of mine is false, and a particular belief of yours is true, then they

are not the same belief’ (1978; pp.4). This does not equate to the non-identity

principle, the clause ‘when these instantiations occur at the same time’2 must be

added, which rules our its application in any of Stichs examples.

To conclude, Stich is unsuccessful in arguing against the folk psychological

category of belief. His arguments, whilst drawn from a sensible principle, that of

psychological autonomy, are built upon a highly flawed premise that attempts to

use obvious intuition that could be considered folk psychology to disprove

obvious intuition that is folk psychology. Indeed, to me the four examples that he

uses in his argument serve more to support the folk psychological category of

belief than to disprove it as in each of them the most intuitive and simplest

explanation of the subjects’ actions is that they are caused by their beliefs.

Bibliography

S. Stich, ‘Autonomous Psychology & the Belief-Desire Thesis’, Monist 61 (1978); rpt. in Bermudez, ed. (2005) & Lycan, ed. (1999).

I. Ravenscroft, ‘Folk Psychology as a Theory’, Stanford Encyclopedia of Philosophy

(2004)

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2Inclusion of ‘by different people’ is supplementary to this main addition, as a single person

cannot have conflicting two beliefs conflicting in truth-value on the same subject at the same time.

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