Social Externalism and Varieties of Content

1
Social Externalism and Varieties of Content

• Advanced Topics in Mind and Knowledge Lecture 3

2
Recap of Twin Earth

• Earth and Twin Earth are identical in every way
  except for the composition of water.
• When Oscar on Earth says water he means H2O,
  whereas when Twin Oscar on Twin Earth says
  water he means XYZ.
• Oscar and Twin Oscar are exact physical and
  therefore psychological duplicates.
• Therefore, meanings arent just in the head
  they are (partly) individuated by the environment!

3
Linguistic Content and Mental Content

• Burge sought to extend Putnams externalist
  arguments to apply to mental as well as
  linguistic content
• The sentences we say express our beliefs, so the
  contents of our beliefs are the contents of the
  sentences.
• Beliefs are individuated by their contents.
• Therefore, if linguistic content is partly
  individuated by the environment then so is mental
  content.

4
Extending Twin Earth

• Burge also extended Putnams externalist
  conclusion to show that
• We can run externalist thought experiments for
  non-natural kind terms.
• Linguistic and mental contents are dependent upon
  social facts about language use in a community,
  as well as physical ones about microstructure.
• Principal source for these claims is the
  Arthritis in the Thigh thought experiment.

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Arthritis in the Thigh I

• Alf has many true beliefs about arthritis,
  including that he has it in his hands, but also
  falsely believes that he has arthritis in his
  thigh.
• This belief must be false, as arthritis is an
  inflammation of the joints (just look it up in a
  medical dictionary).
• If Alf said to his doctor I have arthritis in
  the thigh he would be wrong, and the doctor
  would presumably correct him.
• Now imagine a counterfactual situation where Alf
  is intrinsically identical (he has the same
  internal states and history), but he grew up in a
  community where the word arthritis is applied
  to both arthritis and rheumatoid ailments outside
  of the joints, such as in the thigh.

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Arthritis in the Thigh II

• In the counterfactual situation, when Alf says I
  have arthritis in the thigh he is speaking
  truly, but does not possess the concept of
  arthritis.
• Instead, when using the word arthritis he is
  expressing some other concept, such as
  tharthritis.
• Tharthritis can occur in or outside the joints
  (just ask anyone in Alfs linguistic community
  who knows about it), so Alfs statement is true.

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Arthritis in the Thigh III

• All the intrinsic facts about the real and
  counterfactual Alfs are the same, but their
  beliefs are not the same they express different
  concepts, and hence have different truth values.
• Therefore, mental content must be determined at
  least partly by the environment.
• Note that this thought experiment really has
  nothing to do with arthritis we can construct
  equivalent cases across all sorts of non-natural
  kind terms such as brisket, mortgage, red,
  and sofa.

8
Reconstructing Burges Argument

• Given Alfs general competence with the word
  arthritis and his disposition to e.g. assert I
  have arthritis in the thigh, its right to
  ascribe to him the false belief that he has
  arthritis in his thigh.
• In the real case, Alf has the concept arthritis,
  which he misapplies to produce a false sentence..
• In the counterfactual case, Alf has the concept
  tharthritis, which he correctly applies to
  produce a true sentence.
• Arthritis has different meanings in the two
  cases, as it applies to different (albeit
  overlapping) groups of things.
• Beliefs share their contents with the sentences
  the are expressed by, and are individuated by the
  truth conditions of their contents.
• Therefore, Alfs mental content is partly
  individuated by his environment.

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Externalist Thought Experiments

• According to Burge (1996, p.343) their "common
  strategy is to hold constant the history of the
  person's bodily motion, surface stimulations, and
  internal chemistry. Then, by varying the
  environment with which the person interacts while
  still holding constant the molecular effects on
  the person's body, one can show that some of the
  person's thoughts vary. The upshot is that which
  thoughts one has ... is dependent on relations
  one bears to one's environment."

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Responding to Externalist Thought Experiments I

• Here are a range of possible responses to the
  Twin Earth and Arthritis in the Thigh thought
  experiments
• Strong externalists take them at face value, to
  show that most or even all content is broad, i.e.
  individuated by environmental as well as
  intrinsic factors.
• Strong internalists claim that the thought
  experiments fail to show that any content is
  broad. For example, Tim Crane (1991) claims that
  there is no reason to think that Alf has
  different concepts in both situations as his
  dispositions remain the same.

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Responding to Externalist Thought Experiments II

• In the middle, there are a number of more
  moderate positions which recognise both narrow
  and broad content, e.g.
• Moderate internalism, according to which narrow
  contents plus environments determine broad
  contents.
• Moderate externalism, according to which narrow
  content is fixed by external factors.
• Two factor theories, which recognise and assign a
  role to both narrow and broad content.

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Externalism and Narrow Content

• Roughly
• Strong Internalism Narrow only.
• Moderate Positions Narrow and Broad.
• Strong Externalism Broad only.
• Key concept in evaluating externalism regarding
  mental content is that of narrow content can
  thoughts be individuated by narrow content alone?
  What is it like? Does it exist at all?
• Over the next two weeks well be examining some
  philosophers attempts to give positive answers
  to these questions.