Topic:  Yablo and Robb

Yablo’s “Mental Causation”

1.

*Yablo begins with some historical comments, claiming that non-reductive physicalism has not escaped the epiphenomenal worries that haunted Descartes’ substance dualism.  Again, epiphenomenalism can be generated by utilizing exclusion principles, dualism, and physical closure.  Yablo provides the following Exclusion Argument for epiphenomenalism:

    (1)  If an event x is causally sufficient for an event y, then no event x* distinct from x is causally relevant to y (exclusion).
    (2)  For every physical event y, some physical event x is causally sufficient for y (physical determinism).
    (3)  For every physical event x and mental event x*, x is distinct from x* (dualism).
    (4)  So:  for every physical event y, no mental event x* is causally relevant to y (epiphenomenalism). (pp. 247-248)

*Yablo notes that there are actually two epiphenomenal worries:  a token (event) worry and a type (property) worry.  This distinction should already be familiar to us--the token worry is solved by Davidson’s AM, but the type worry is not (the type worry is what I have called the “in virtue of” objection).

*Yablo’s proposed solution to the type worry is that properties related as determinable-determinate are exceptions to exclusion principles.

2.

*Example of properties related as determinable-determinate:  red-crimson.

*Yablo states the metaphysical idea behind determination is:

     “P determines Q (P>Q) only if:
    (i)  necessarily, for all x, if x has P then x has Q; and
    (ii) possibly, for some x, x has Q but lacks P.” (p. 252)

    --Note that this is only a necessary condition for determination.

    --Yablo, citing Kripkean reasons, notes that the determination relation should be thought of as a metaphysical relation, rather
    than in terms of conceptual entailment. (pp. 252-253)

3.

Q:  Can my physical properties be determinates of my thinking properties?

Yablo’s Answer:  Yes.  He thinks that this answer is suggested by the asymmetric necessitation of the mental by the physical.

    “Such a view is in fact implicit in the reigning orthodoxy about mind-body relations, namely, that the mental is supervenient on,
    but multiply realizable in, the physical.” (p. 254)

4.

*An example:  Sophie, the red-pecking pigeon.  This example is used to show that properties related as determinable-determinate do not causally exclude one another.

    --If this weren’t the case, then we’d have exclusion all over the place
    “Almost whenever a property Q is prima facie relevant to an effect, a causally sufficient determination Q’ of Q can be found
    to expose it as irrelevant after all.” (p. 258)

    --Worry:  Would only super-determinate properties ever be causally relevant?

    --Yablo finds these possibilities unacceptable and claims that:
    “any credible reconstruction of the exclusion principle must respect the truism that determinates do not contend with their
    determinables for causal influence.” (p. 259)

5.

*Yablo extends determination to particulars (events) as well.  E.g., the bolt’s suddenly snapping is a determinate of its snapping per se.  Why?  Because to snap suddenly is to snap, not simpliciter, but in a certain way. (p. 260)

    --Yablo explains that the essence of a determinate event includes the essences of all the determinable events it falls under. (pp.
    261-262)

6.

*Yablo uses Kripke-style intuitions/arguments to show that mental events and physical events have different modal properties (and hence are not identical).  But, Yablo DOESN’T argue that physical events have weaker essences than the mental events they correspond with.  This would go against supervenience.  For example, Yablo denies Kripke’s “zombie-style” intuitions (e.g., as quoted on p. 266).  Instead, Yablo claims that “the essences of mental events are physically impoverished ... in comparison with their physical bases, mental phenomena are exceedingly modally elastic.” (pp. 268-269)  This agrees with Kripke’s second type of argument (quoted on p. 269) against the identity theorist--this pain could have existed without this particular realization.

    --The fact that the essence of the brain state is richer than the essence of the pain state is used as evidence that the brain state
    determines the pain state.

7.

*This mental-physical token (event) distinctness does not mean that mental events succumb to exclusion principles.  Why not?

    “...rather than competing for causal honors, determinables and their determinates seem likelier to share in one another’s
    success.  Again the application to mental and physical events is anticlimactic.  Unless an arbitrary exception is to be made of
    them, it is no argument at all for the causal irrelevance of, say, a sensation that is occurring in some specific physical way was
    causally sufficient.  With events as with properties, physical determinates cannot defeat the causal pretensions of their mental
    determinables.” (pp. 272-273)

8.

*Yablo’s main conclusion thus far is that physical events do not causally exclude mental events.  This doesn’t mean that mental events are causally relevant.  Further, even though determinables and their determinates do not causally exclude one another, Yablo argues that it very well might be the case that a determinable property is causally relevant in a particular case and not some of its determinates (or vice versa).

    --Yablo:  “causes are expected to be commensurate with their effects:  roughly, they should incorporate a good deal of causally
    important material but not too much that is causally unimportant.” (pp. 273-274)  [This is our, now familiar, point that causation
    has both a sufficiency and a necessity aspect.]

    --In a particular case of causation, a determinable or determinate may be more commensurate with the effect.  So, one or the
    other could win out as the cause.

    --Yablo:  “Then when do we attribute effects to mental causes?  Only when we believe, I can only suppose rightly, that the
    effect is relatively insensitive to the finer details of m’s physical implementation.” (p. 278)

9.

*We see that Yablo attempts to allow for mental causation, by “tweaking” causation:

“Indeterministic scruples aside, everything that happens is in strict causal consequence of its physical antecedents.  But causally necessitating is a different thing from causing, and the physical has no monopoly on causation.” (p. 279)

*Yablo’s picture is in the spirit of the dual explanandum theorist:

    “But maybe we are not misled to think that outcomes effected by their physical antecedents are neither speech nor action, nor
    expressions of any sort of human agency.  Maybe the mistake was to think that outcomes of the kind normally credited to
    human agency are caused by their physical antecedents.” (p. 280)
 

General points/grounds for objections.

Q:  Shouldn’t we have an explanation of why determinables and their determinates do not causally exclude one another?

*We should put further limits on determination, besides one-way necessitation, and these will show that the physical doesn’t determine the mental.
 

Robb’s “The Properties of Mental Causation”

I.

Terminology:  a causally relevant property is that “in virtue of” which an event brings about some effect.

*Problem:  Given physical closure, how can mental properties be causally relevant?

II.

*Davidson’s AM denies the causal relevance of the mental.

    --Robb claims that Fodor and LePore/Loewer style solutions don’t work, because neither nomological nor counterfactual
    dependence is enough for causal relevance--they are both compatible with epiphenomenalism. (p. 181)  (His clapping/electrical
    field example is supposed to show this.)

*There is a more general road to epiphenomenalism (than Davidson’s AM)--it is supposed to come from these two principles:

    “Distinctness: Mental properties are not physical properties.” (p. 182)
        --MR is supposed to get us this.
    “Closure:  every physical event has in its causal history only physical events and physical properties.” (p. 183)
        --We might use an Exclusion Principle to reach Closure. (p. 184)

*Robb’s goal is to show that, in spite of appearances, Relevance, Distinctness, and Closure are compatible.

III.

*Can mental-physical supervenience alone reconcile Relevance with Distinctness and Closure?

    --Supervenient causation would still violate Closure.

    --Maybe all supervenient properties, not just mental ones, are causally irrelevant.

    --How does supervenience secure Relevance?

IV.

*Two senses of ‘property’:  as a type (e.g., universal or class) or as a token (e.g., abstract particular or trope).

*Robb thinks Relevance, Distinctness, and Closure can be reconciled by utilizing tropes.  He asserts what he calls a ‘trope monism.’  As Davidson thought all events (mental events in particular) are physical events, Robb holds that all tropes (physical tropes in particular) are physical tropes.

    --Robb’s claim:  tropes are “the properties of causation.” (p. 187)

    --Robb’s solution to the apparent inconsistency of the 3 principles, is that there is an equivocation on the word ‘property’.  Once
    we disambiguate the terms, we see that the new principles are:

    “Relevance:  mental tropes are (sometimes) causally relevant to physical events
    Distinctness:  mental types are not physical types
    Closure:  every physical event has in its causal history only physical events and physical tropes.” (p. 188)

*On p. 188, Robb provides two assumptions from which trope monism entails supervenience.  But, trope monism, unlike the supervenience-proposal, does not violate Closure.  More importantly:

    “...the trope solution shows the relevance of Supervenience to mental causation.  The reason why the supervenience of mental
    on physical types secures the causal relevance of the mental is that, on Supervenience (as the trope theory explains it), mental
    tropes just are the tropes that are agreed to be unproblematically relevant to physical effects.” (p. 189)

*Robb makes three applications of his trope solution:

    1)  Exclusion-Driven Causal Competition:  Mental tropes do not causally compete with physical tropes, because they are
    physical tropes.

    2)  Kim’s Causal Inheritance Principle:  It is easy to see why higher-level properties share the causal powers of their
    realizers--these types share a trope, and the causal powers inhere in that trope.

    3)  Second-Order Impotence:  While second-order property types are distinct from their embedded first-order property types,
    they share tropes.  Then, if the first-order trope is causally relevant, so is the second-order trope.

*Robb responds to two objections.

Objection 1:  We can raise the “in virtue of” objection at the trope level.  Does this trope, which is both mental and physical, cause in virtue of falling under physical or mental types?  If only the former, then we’re back to epiphenomenalism.

    Response:  “A causally relevant property F simply does not have various aspects such that one can legitimately ask whether
    some but not others are responsible for F’s being causally relevant.” (p. 191)

Objection 2:  If tropes are the properties of causation, then there are too many causes.  E.g, there is the over-70-dB trope, 80-dB trope, etc.

    Response:  All these allegedly distinct tropes are actually one.  Tropes are causes however described.  And it doesn’t make
    sense to think of types as causally relevant. (p. 192)

*Of course, one might deny that tropes exist.  But Robb also points out that if tropes are the best, are only solution, to mental causation, then that is strong reason to believe in them.