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Ideas of John Perry, by Text

[American, fl. 1975, Professor at Standford University.]

1970 The Same F
n12 p.99 Statements of 'relative identity' are really statements of resemblance
     Full Idea: Statements of 'relative' identity are not identity statements at all, but what I would prefer to call 'statements of resemblance' or 'common property staztements'.
     From: John Perry (The Same F [1970], n12)
     A reaction: This seems like a neat way to sweep the problem from our sight. There remains a nervous metaphysical problem, though, because something seems to be identical when we spot a resemblance. Even two shades of red have something identical in them.
1979 The Problem of the Essential Indexical
p.28 Tense is essential for thought and action
     Full Idea: Tense plays a crucial role in thought and action.
     From: report of John Perry (The Problem of the Essential Indexical [1979]) by Robin Le Poidevin - Past, Present and Future of Debate about Tense 3 a
     A reaction: This is important, because much of our metaphysics is dominated by a detached 'scientific' description of reality, which is given a rather passive character. If processes take centre stage, which they should, then our own processes are part of it.
p.29 Actual tensed sentences cannot be tenseless, because they can cite their own context
     Full Idea: In the new tenseless theory, no tensed token sentence can be equivalent to a tenseless token, because the former, unlike the latter, draws attention to the context in which it is tokened.
     From: report of John Perry (The Problem of the Essential Indexical [1979]) by Robin Le Poidevin - Past, Present and Future of Debate about Tense 3 a
     A reaction: So the problem about indexicals was worrying fans of the tenseless B-series view of time (and so it should). I'm inclined to translate sentences containing indexicals into their actual propositions, which tend to avoid them. 'Time/person of utterance'.
'Intro' p.167 Indexicals are a problem for beliefs being just subject-proposition relations
     Full Idea: The essential indexical is a problem for the view that belief is a relation between subjects and propositions conceived as bearers of truth and falsity.
     From: John Perry (The Problem of the Essential Indexical [1979], 'Intro')
     A reaction: My immediate reaction would be that it depends on how you conceive of 'propositions'. If they are objective, you have a problem. I take them to be subjective events in brains, and the indexical meaning to be evident within the proposition.
'Intro' p.167 If we replace 'I' in sentences about me, they are different beliefs and explanations of behaviour
     Full Idea: If I leave a trail of sugar, and realise 'that I am making a mess', ...when we replace the word 'I' with other designations of me, we no longer have an explanation of my behaviour, or an attribution of the same belief, so it is an 'essential indexical'.
     From: John Perry (The Problem of the Essential Indexical [1979], 'Intro')
     A reaction: [compressed] A famous observation of Perry's, which leads him to challenge traditional accounts of belief and of propositions. I don't think I see a problem, if we have a thoroughly non-linguistic account of essentially unambiguous propositions.
'Obvious' p.181 Indexicals individuate certain belief states, helping in explanation and prediction
     Full Idea: We use sentences with indexicals or relativized propositions to individuate belief states, for the purposes of classifying believers in ways useful for explanation and prediction.
     From: John Perry (The Problem of the Essential Indexical [1979], 'Obvious')
     A reaction: He goes on to apparently connect this with some sort of moral integrity involved in 'owning up' to the fact that the person in question is you (who has spilled the sugar etc.).
'Prob' p.172 Indexicals reveal big problems with the traditional idea of a proposition
     Full Idea: The problem of the essential indexical reveals that something is badly wrong with the traditional doctrine of propositions.
     From: John Perry (The Problem of the Essential Indexical [1979], 'Prob')
     A reaction: See the reaction to 12149. The traditional view of propositions, or at least Russell's view, seems to be that they are same as facts, which strikes me as daft. I take propositions to be brain events, probably expressed in mentalese.
2001 Knowledge, Possibility and Consciousness
§1.2 p.6 Identity is a very weak relation, which doesn't require interdefinability, or shared properties
     Full Idea: The truth of "a=b" doesn't require much of 'a' and 'b' other than that there is a single thing to which they both refer. They needn't be interdefinable, or have supervenient properties. In this sense, identity is a very weak relation.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §1.2)
     A reaction: Interesting. This is seeing the epistemological aspects of identity. Ontologically, identity must invoke Leibniz's Law, and is the ultimately powerful 'relation'. A given student, and the cause of a crop circle, may APPEAR to be quite different.
§1.2 p.6 Brain states must be in my head, and yet the pain seems to be in my hand
     Full Idea: The brain state will involve certain parts of the brain, whereas my feeling of pain seems to be located in my hand insofar as it has a bodily location.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §1.2)
     A reaction: This seems important to me. The brain is a ventriloquist. Perry implies that pain is quasi-disembodied, but it isn't, it is just experienced as IN the hand. Perhaps it is in the hand? Cutting the nerves loses contact with the pain.
§2.4 p.38 We try to cause other things to occur by causing mental events to occur
     Full Idea: We try to cause other things to occur by causing mental events to occur.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §2.4)
     A reaction: A small and obvious, but important, point. Mental causation isn't just thoughts leading to physical happenings. Here Perry means that events can be designed to cause thoughts, such as a threatening letter. Not much room for epiphenomenalism here.
§3.1 p.48 It seems plausible that many animals have experiences without knowing about them
     Full Idea: It seems quite plausible to me that many animals have experiences without knowing about them.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §3.1)
     A reaction: I agree, which makes us acknowledge levels of consciousness, which probably applies to human experience as well. The simplest idea is to distinguish between experiences which involve concepts, and those which don't. Animals sometimes appear surprised.
§3.2 p.51 Although we may classify ideas by content, we individuate them differently, as their content can change
     Full Idea: Although we classify ideas by content for many purposes, we do not individuate them by content. The content of an idea can change.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §3.2)
     A reaction: As the compiler of this database, I find this very appealing. The mind works exactly like a database. I have a 'file' (Perry's word) marked "London", the content of which undergoes continual change. I am a database management system.
§3.2 p.54 A sharp analytic/synthetic line can rarely be drawn, but some concepts are central to thought
     Full Idea: Although there is seldom a sharp analytic/synthetic distinction to be drawn in the case of our concepts, there are clearly things that are more and less central.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §3.2)
     A reaction: Most Americans seem enslaved to Quine on this one, so it is nice to see the obvious being stated for once. Human thought is an organic offshoot of the natural world. To think it is all arbitrary and changeable is human arrogance.
§4.2 p.78 If epiphenomenalism just says mental events are effects but not causes, it is consistent with physicalism
     Full Idea: Epiphenomenalism is usually considered to be a form of dualism, but if we define it as the doctrine that conscious events are effects but not causes, it appears to be consistent with physicalism.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §4.2)
     A reaction: Interesting. The theory was invented to put mind outside physics, and make the closure of physics possible. However, being capable of causing things seems to be a necessary condition for physical objects. An effect in one domain is a cause in another.
§4.3 p.88 If physicalists stick with identity (not supervenience), Martian pain will not be like ours
     Full Idea: The physicalist should not retreat to causal supervenience but should stick with identity. This means we will have to accept that a Martian and I (when in pain) are not in the same phenomenal state.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §4.3)
     A reaction: We naturally presume that frogs feel pain as we do, but many different phenomenal states could lead to the same behavioural end. Only an unpleasant feeling is required. A foul smell would do. Frogs could function with inverted qualia, too.
§8.1 p.170 The intension of an expression is a function from possible worlds to an appropriate extension
     Full Idea: In possible-worlds semantics, expressions have intensions, which are functions from possible worlds to appropriate extensions (names to individuals, n-place predicates to n-tuples, and sentences to truth values, built from parts).
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: Interesting. Perry distinguishes 'referential' (or 'subject matter') content, which is prior to the link to extensions - a link which creates 'reflexive' content. He is keen that they should not become confused. True knowledge is 'situated'.
§8.1 p.170 A proposition is a set of possible worlds for which its intension delivers truth
     Full Idea: The proposition expressed by a sentence can be thought of as a set of possible worlds, the worlds for which its intension delivers truth.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: It has always struck me as important to hang on to the concept of a 'proposition' (over and above sentences). This idea gives a metaphysics for the concept, and the 'language of thought' offers appropriate brain structures. A neat picture.
§8.1 p.170 Possible worlds thinking has clarified the logic of modality, but is problematic in epistemology
     Full Idea: Using possible worlds to model truth-conditions of statements has led to considerable clarity about the logic of modality. Attempts to use the system for epistemic purposes, however, have been plagued by problems.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: Presumably what lurks behind this is a distinction between what is logically or naturally possible, and what appears to be possible from the perspective of a conscious mind. Is there a possible world in which I can fly?
§8.1 p.170 Possible worlds are indices for a language, or concrete realities, or abstract possibilities
     Full Idea: Possible worlds can be thought of as indices for models of the language in question, or as concrete realities (David Lewis), or as abstract ways the world might be (Robert Stalnaker), or in various other ways.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: I strongly favour the Stalnaker route here. Reducing great metaphysics to mere language I find abhorrent, and I suspect that Lewis was trapped by his commitment to strong empiricism. We must embrace abstractions into our ontology.
§8.1 p.171 Prior to Kripke, the mind-brain identity theory usually claimed that the identity was contingent
     Full Idea: Advocates of the mind-body identity theory typically claimed that identity between particular mental states and brain states was contingent, until Kripke argued persuasively that identity is always necessary.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: Kripke wanted to argue against the identity theory, but what he seems to have done is reformulate it into a much more powerful version (involving necessary identity).
§8.1 p.175 Truth has to be correspondence to facts, and a match between relations of ideas and relations in the world
     Full Idea: I think knowledge and truth are a matter of correspondence to facts, despite all the energy spent showing the naïveté of this view. The connections of our ideas in our heads correspond to relations in the outside world.
     From: John Perry (Knowledge, Possibility and Consciousness [2001], §8.1)
     A reaction: Yes. Modern books offer the difficulties of defining 'correspondence', and finding an independent account of 'facts', as conclusive objections, but I say a brain is a truth machine, and it had better be useful. Indefinability doesn't nullify concepts.
2001 Reference and Reflexivity
p.249 Indexical thoughts are about themselves, and ascribe properties to themselves
     Full Idea: Perry's newer token-reflexive framework says indexical thoughts have token-reflexive content, that is, thoughts that are about themselves and ascribe properties to themselves. …They relate not to the subject, but to the occurrence of a thought.
     From: report of John Perry (Reference and Reflexivity [2001]) by François Recanati - Mental Files 18.1
     A reaction: [There seem to be four indexical theories: this one, Recanati's, the earlier Kaplan-Perry one, and Lewis's] Is Perry thinking of second-level thoughts? 'I'm bored' has the content 'boredom' plus 'felt in here'? How does 'I'm bored' refer to 'I'm bored'?