In 2008, I wrote a post on Stalnaker on self-location,
in which I attributed a certain position to Stalnaker and raised some
objections. But the position isn't actually Stalnaker's. (It might be
closer to Chisholm's). So here is another attempt at figuring out
Stalnaker's view. (I'm mostly drawing on chapter 3 of Our Knowledge
of the internal world (2008), chapter 5 of Context (2014),
and a forthcoming paper called "Modeling a perspective on the world"
(2015).)
In "Ramseyan
Humility", Lewis argues for a thesis he calls "Humility". He never
quite says what that thesis is, but its core seems to be the claim
that our evidence can never rule out worlds that differ from actuality
merely by swapping around fundamental properties. Lewis's argument, on
pp.205-207, is perhaps the most puzzling argument he ever gave.
Lewis begins with some terminology.
In The Logic of Decision, Richard Jeffrey pointed out that
the desirability (or "news value") of a proposition can be usefully
understood as a weighted average of the desirability of different ways
in which the proposition can be true, weighted by their respective
probability. That is, if A and B are incompatible propositions,
then
(1) Des(AvB) = Des(A)P(A/AvB) + Des(B)P(B/AvB).
So desirabilities are affected by probabilities. If you prefer A
over B and just found out that conditional on their disjunction, A is
more likely then B, then the desirability of the disjunction goes
up. That seems right.
Superficially, modal auxiliaries such as 'must', 'may', 'might', or
'can' seem to be predicate operators. So it is tempting to interpret
them as functions from properties to properties: just as 'Alice jumps'
attributes to Alice the property of jumping, 'Alice can jump'
attributes to her the property of being able to jump, 'Alice may jump'
attributes the property of being allowed to jump, and so on.
Perhaps the biggest obstacle to this approach comes from quantified
constructions. If 'Alice may jump' attributes to Alice the property of
being allowed to jump, then 'one of us may jump' should say that one
of us has the property of being allowed to jump. But while this is one
possible reading of the sentence, 'one of us may jump' also has a
reading on which it states that it is permissible that one of us
jumps. There is a kind of de re/de dicto ambiguity here, which
suggests that 'may' can not only apply to properties but also to
propositions.
Let's say that an act A is subjectively better than an
alternative B if A is better in light of the agent's information; A is
objectively better if it is better in light of all the
facts. The distinction is easiest to grasp in a consequentialist
setting. Here an act is objectively better if it brings about more
good -- if it saves more lives, for example. A morally conscientious
agent may not know which of her options would bring about more
good. Her subjective ranking of the options might therefore go by the
expectation of the good: by the probability-weighted average of the
good each act might bring about.
"The Philosopher's Index" is a commercial software once widely
used to search for articles in philosophy journals. These days
it is
generally easier and faster to
search on the open internet. (Even the company behind the Philosopher's Index is not quite sure why the Index is still needed.) However, there is one thing the
Index has that can't be found anywhere else: many of its entries
contain abstracts of books and articles, apparently provided by the
authors themselves. These abstracts are often not part of the
published versions, and they can be quite useful to get an
authoritative summary, or to see what the author considered to be the
main point of a paper.
If you spin a wheel of fortune, the outcome -- red or black -- depends
on the speed with which you spin. As you increase the speed,
the outcome quickly cycles through the two possibilities red and
black. As a consequence, any reasonably smooth probability distribution
(or frequency distribution) over initial speed determines an
approximately equal probability (frequency) for red and black. Here is
an example of such a distribution, taken from Strevens.
I've been asked to review Michael Strevens's new book,
Tychomancy. This motivated me to have another look at his
earlier book Bigger than Chaos.
The aim of Bigger than Chaos is to explain how apparently
chaotic interactions in highly complex systems often give rise to
simple large-scale regularities, such as the laws of thermodynamics,
the stability of predator/prey population levels, or the economic
cycle. The basic explanatory strategy, which Strevens calls enion
probability analysis (EPA), consists in aggregating the
probabilistic dynamics for the individual components of a complex
system into a probabilistic dynamics for macro-level features of the
system.
Plausible moral theories should be agent-relative. They should
permit us to care more about close friends than about distant
strangers. They can prohibit killing ten innocent people even in
circumstances where eleven innocent people would otherwise be killed
by somebody else. They might say that it would be right for Alice to
dance with Bob, but wrong for Bob to dance with Alice.
But how should we think about agent-relative values? It may seem
that the state of affairs in which Alice dances with Bob is either
right or not right. How could it be right relative to Alice but wrong
relative to Bob? Or consider a case where I can prevent you from
killing eleven by killing ten myself. If it is wrong that you kill the
eleven, then surely I have a moral reason to see to it that you don't
kill the eleven, just as I have a moral reason to see to it that I
don't kill the ten. Moreover, presumably it is worse if you kill
eleven than if I kill ten. So shouldn't my reason to prevent you from
killing the eleven outweigh my reason to not kill the ten?
Often the factors that determine a phenomenon don't determine it
uniquely. Sometimes this changes the phenomenon itself.
Take language. Plausibly, the meanings of our words are somehow determined by
patterns of use, but these patterns aren't specific enough to fix,
say, a unique extension or intension for our language. There is a
range of precise meaning assignments all of which fit our use equally
well. One might leave it at that and say that it is indeterminate
which of these precise languages we speak. But this misses
something. It misses the fact that we don't speak a precise
language. For example, in a precise language, "Mount Everest has sharp boundaries"
would be true, but in English it is false. The logic of a precise
language would (arguably) be classical, but the logic of English is
not.