Polling in Metaphysics, part II

In a previous post, I summarized some findings on a survey I ran in my metaphysics course on the Ship of Theseus.  Last week, I ran another survey on the Problem of Temporary Intrinsics.  Below are the survey as well as data on the results.  As with the previous survey, this one led to some rather unexpected results.  Questions/comments are of course welcome.

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Handout:

Consider the following passage from a recent book by Helen Beebee and Julian Dodd:

Objects persist through changes in their intrinsic properties: that is, in properties—such as having a bent shape and having a straight shape—that objects have purely in virtue of how they are, independently of any other object.  So, for example, if Eleanor at time t is sitting down and then at t + 1 stands up, she persists through the change from having a bent shape to having a straight shape….  For Eleanor to persist through this change, she would seem to have to somehow instantiate incompatible properties: that is, be both bent and straight.  But nothing can be both bent and straight, so it is mysterious how such an intrinsic change can occur.  To put the problem another way, Leibniz’ Law—the indiscernability of identicals—states that [necessarily] if a and b are identical, then a and b have all the same properties.  And this law would seem to be correct.  If, for instance, Eleanor has brown hair and Holly has blonde hair, then we may justifiably conclude that Eleanor and Holly are not one and the same: any difference in properties had by Eleanor and Holly entails that Eleanor and Holly are not identical.  The problem, of course, is that analogous reasoning would seem to apply to our case of everyday persistence through time: Eleanor cannot be said to survive getting up because Eleanor-sitting and Eleanor-standing have different properties, and hence must be different entities.  It would seem to be impossible for a single thing to survive this change. [Reading Metaphysics (Blackwell: 2007), 208]

We can formalize the argument from Beebee and Dodd as follows:

1. At time t, Eleanor has the property sitting.
2. At time t + 1, Eleanor has the property standing.
3. Sitting and standing are incompatible (and thus different) properties.
4. Leibniz’ Law—if a and b are identical, then a and b have all the same properties.
5. Therefore, Eleanor at t and Eleanor at t + 1 are not identical.
6. Therefore, Eleanor cannot survive the change involved in standing.

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Questions:

For each premise of this argument, indicate whether you think that premise is true or false:

Premise (1) is   True: ____       False: ____

Premise (2) is   True: ____       False: ____

Premise (3) is   True: ____       False: ____

Premise (4) is   True: ____       False: ____

For each of the argument’s conclusions, indicate whether you think the inference to that inference is valid (that is, would the conclusion follow if all the premises on which it depended were true):

The inference to (5) is:  Valid: ____      Invalid: ____

The inference to (6) is:  Valid: ____      Invalid: ____

Is the argument sound?

Sound: ____     Unsound: ____

Can things survive change?

Yes: ____        No: ____

If you think that the argument is unsound, indicate where you think it goes wrong;

If you think that the argument is sound, how do you account for the appearance of change (i.e., for the fact that things seem to change even though they can’t really change)?

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Results:

Of the 28 students who filled out this survey, six students (21.5%!) said that the argument was sound.  All six of these students also indicated that all four premises were true, and that each inference in the argument was valid.  Drawing on the Chisholm reading from the previous week, one student who denied the possibility of change said that Eleanor at t and Eleanor at t+1 are only identical in the ‘loose and popular sense’, but that nothing can survive a change in the ‘strict and philosophical sense of identity.’  Another student who evaluated the argument as sound gave the following evolutionary account for the appearance of change:

I believe that our brains perceive things as consistent through time because it is functional.  If a brain had evolved that could perceive the amount of change occurring at all points in time it couldn’t eat, reproduce, etc… and that organism would not be viable in a natural environment.  However, just because we can’t perceive something doesn’t mean it’s not happening.  Logically we know that change occurs constantly, but we only see certain kinds of change that were evolutionarily useful to us at one point; therefore it appears that things remain constant except for some small particulars.  Also, the fact that our species is successful indicates that part of our biology has caused us to have the desire to survive.  I think the evolutionarily derived fear of our non-existence causes the resistant to accepting this argument.

A seventh student should also, I believe, be included in this group (thereby bringing the percentage up to 25%).  This student indicated that both inferences were valid but denied the truth of all four premises.  In the space to explain why he thought the argument was unsound, the student indicated that he thought that neither standing nor sitting are properties (what he said was a property was having a flexible spine so that one could sit or stand).  However, he also wrote that if we do assume that standing and sitting are properties, “it would seem that this argument is both sound and valid.”

     Ten students said that all four premises of the argument were true but claimed that the argument was unsound.  All ten students in this group said that at least one inference in the argument was invalid.  Two students said that both the inference to (5) and the inference to (6) were invalid.  One student claimed that only the inference to (5) was invalid, and seven students thought that while the inference to (5) was valid, the inference to (6) was invalid.  In their explanation for where the argument went wrong, two of these seven students indicated that Eleanor only changed qualitatively not numerically, despite agreeing that the inference to (5) from true premises was valid. 

     Eleven students rejected at least one of the four premises as false:  two rejected both (1) and (2), eight rejected (3), and two rejected (4).  Of these eleven students, three thought that both inferences were true; six students said that while the inference to (5) is valid, the inference to (6) was invalid.  When combined with the previous group of students who accepted all four premises as true, this means that 13 students out of the total of twenty-eight rejected the inference to (6) as invalid. I was intrigued that these students were willing to admit that Eleanor at t was numerically distinct from Eleanor at t + 1 but denied that, as a consequence, Eleanor cannot survive the change involved in standing.  During the discussion period, a number of the students who claimed the inference to (6) was invalid said they answered as they did because while they were sure that the argument went wrong somewhere, they weren’t sure where it went wrong and simply chose the inference to (6). 

     So one interesting result of this experiment is seeing students struggle with the implications that follow from views they hold.    In discussion in class today before this week's survey (on the Statue/Lump co-location case), one student said that these surveys make him 'uncomfortable'.  When I asked him to explain, he said that they show him that he's committed to conclusions that he doesn't want to endorse. 

Comments

[Trainee Philosopher]

I'm a grad student tutoring epistemology this year, and I'd really like to try out some polling as pedagogy. I dabbled with the technique last year when instructing a philosophy of mind module. In my first class I informally polled students (counting hands) on a range of topics and put the results up on the board for us to discuss. The thing is, this year my students will have already had a lecture before I see them, so I'm wondering whether surveying will still be a worthwhile teaching technique. On p. 48 of Nadelhoffer and Nahmias' paper they stress that surveys should be carried out before any discussion or reading of the topic. Any thoughts on this would be greatly appreciated.

[Kevin Timpe]

If you meet with the students in your discussion section after the lecture for that week, perhaps in any given week you could give them a survey on the topic for the following week. That way, they would be less likely to have been exposed to philosophical work on the topic of the survey.