## 1. Challenging Choice Situations, Problematic Preference Structures, and Dynamic Choice Problems



Effective choice over time can be extremely difficult given certain
challenging choice situations or problematic preference structures,
such as the ones described below. As will become apparent, these
choice situations or preference structures can prompt a series of
decisions that serve one's large-scale, ongoing concerns very
badly. (Note that, as is standard in dynamic choice theory, the
discussion in this entry leaves room for non-selfish preferences and
concerns; it thus leaves room for the possibility that one can be
determined to serve one's preferences and concerns as well as
possible without being an egoist.)


### 1.1 Incommensurable Alternatives



Let us first consider situations that involve choosing between
incommensurable alternatives.



According to the standard conception of incommensurability explored
extensively by philosophers such as Joseph Raz and John Broome (see,
for example, Raz 1986 and Broome 2000), two alternatives are
incommensurable if neither alternative is better than the other, nor
are the two alternatives equally good.



It might seem as though the idea of incommensurable alternatives does
not really make sense. For if the value of an alternative (to a
particular agent) is neither higher nor lower than the value of
another alternative, then the values of the two alternatives must, it
seems, be equal. But this assumes that there is a common measure that
one can use to express and rank the value of every alternative; and,
if there are incommensurable alternatives, then this assumption is
mistaken.



Now consider the following: If all alternatives were commensurable,
then whenever one faced two alternatives neither of which was better
than the other, slightly improving one of the alternatives would, it
seems, 'break the tie' and render one alternative, namely
the improved alternative, superior. But there seem to be cases in
which there are two alternatives such that (i) neither alternative is
better than the other and (ii) this feature is not changed by slightly
improving one of the alternatives. Consider, for example, the
following case: For Kay, neither of the following alternatives is
better than the other:



> 
> 
> (A1) going on a six-day beach vacation with her children
> 
> 
> 
> (A2) taking a two-month oil-painting course.
> 
> 
> 



Furthermore, although the alternative



> 
> (A1+) going on a seven-day beach vacation with her children
> 



is a slight improvement on A1, A1+ is not better than A2.
This scenario seems possible, and if it is, then we have a case of
incommensurable alternatives. For, in this case, A1 is not better than
A2, A2 is not better than A1, and yet A1 and A2 are not equally good.
If A1 and A2 were equally good, then an improvement on A1, such as
A1+, would be better than A2. But, for Kay, A1+
is not better than A2.



It is often supposed that incommensurable alternatives must be
incomparable. But things are complicated once it is recognized that
there is conceptual room for two alternatives that are not comparable
as one better than the other or as equally good (and so are
incommensurable according the conception of incommensurability
identified above) to be comparable as 'in the same league'
or 'on a par,' and thus not altogether incomparable, as
would be the case if there were no positive relation connecting the
overall value of each option (see Chang 2002). For the purposes of
this discussion, the question of whether incommensurable alternatives
are invariably incomparable can be put aside, since the dynamic choice
problem that will be discussed in relation to incommensurability
applies regardless of whether the incommensurable options at issue are
incomparable or are instead comparable as on a par.



Although there is still some controversy concerning the possibility of
incommensurable alternatives (compare, for example, Raz 1997 and Regan
1997), there is widespread agreement that we often *treat*
alternatives as incommensurable. Practically speaking, determining the
value of two very different alternatives in terms of a common measure,
even if this is possible, may be too taxing. It is thus often natural
to treat two alternatives as though they are neither equal nor one
better than the other.



The existence or appearance of incommensurable alternatives can give
rise to dynamic choice problems. Consider Abraham's case, as
described by John Broome in his work on incommensurability:



> 
> God tells Abraham to take his son Isaac to the mountain, and there
> sacrifice him. Abraham has to decide whether or not to obey. Let us
> assume this is one of those choices where the alternatives are
> incommensur[able]. The option of obeying will show submission to God,
> but the option of disobeying will save Isaac's life. Submitting
> to God and saving the life of one's son are such different
> values that they cannot be weighed determinately against each other;
> that is the assumption. Neither option is better than the other, yet
> we also cannot say that they are equally good. (Broome 2001, 114)
> 



Given that the options of submitting to God and saving Isaac are
incommensurable (and even if they were only incommensurable as far as
a reasonable person could tell), Abraham's deciding to submit to
God seems rationally permissible. So it is easy to see how
Abraham's situation might prompt him to set out for the mountain
in order to sacrifice Isaac. But it is also easy to see how, once at
the foot of the mountain, Abraham might decide to turn back. For, even
though, as Broome puts it, "turning back at the foot of the
mountain is definitely worse than never having set out at all"
since "trust between father and son [has already been] badly
damaged" (2001, 115), the option of saving Isaac by turning back
and the option of submitting to God and sacrificing Isaac may be
incommensurable. This becomes apparent if one recalls Kay's case
and labels Abraham's above-mentioned options as follows:



> 
> 
> (B1) saving Isaac by turning back at the foot of the mountain
> 
> 
> 
> (B1+) saving Isaac by refusing to set out for the
> mountain
> 
> 
> 
> (B2) submitting to God and sacrificing Isaac.
> 
> 
> 



Even though B1+ is better than B1, both B1+ and
B1 may be incommensurable with B2. But if B1 is incommensurable with
B2, then Abraham could, once at the foot of the mountain, easily
decide to opt for B1 over B2. Given that B1 is worse than
B1+, Abraham could thus easily end up with an outcome that
is worse than another that was available to him, even if each of his
choices makes sense given the value of the alternatives he faces.



The moral, in general terms, is that in cases of incommensurability
(or cases in which it is tempting to treat two alternatives as
incommensurable), decisions that seem individually defensible can,
when combined, result in a series of decisions that fit together very
poorly relative to the agent's large-scale, ongoing
concerns.


### 1.2 Time-Biased Preferences



Another source of dynamic choice problems is present-biased
preferences.



Like other animals, humans give more weight to present satisfaction
than to future satisfaction. In other words, we discount future
utility. Insofar as one discounts future utility, one prefers, other
things equal, to get a reward sooner rather than later; relatedly, the
closer one gets to a future reward, the more the reward is valued. If
we map the value (to a particular agent) of a given future reward as a
function of time, we get a discount curve, such as in Figure 1:



![Figure 1](figure1.jpg)

Figure 1. The discounted value of a
reward gradually increases as *t*, the time at which the reward
will be available, approaches.




Research in experimental psychology (see, for example, Kirby &
Herrnstein 1995, Millar & Navarick 1984, Solnick et al. 1980, and
Ainslie 2001) suggests that, given how animals, including humans,
discount future utility, there are plenty of cases in which the
discount curves from two rewards, one a small reward and the other a
larger later reward, cross, as in Figure 2:



![Figure 2](figure2.jpg)

Figure 2. Two crossing discount curves,
one tracking the discounted value of a small reward that will be
available at *t*1 and the other tracking the
discounted value of a large reward that will be available at
*t*2.




In such cases, the agent's discounting of future utility induces
a preference reversal with respect to the two possible rewards. When
neither reward is imminent, before the discount curves cross, the
agent consistently prefers the larger later reward over the smaller
earlier reward. But when the opportunity to accept the small reward is
sufficiently close, the discounted value of the small reward catches
up with and then overtakes the discounted value of the larger later
reward. As the discount curves cross, the agent's preferences
reverse and she prefers the small reward over the larger later
reward.



Discounting-induced preference reversals make consistent and efficient
choice over time a challenge. An agent subject to discounting-induced
preference reversals can easily find herself performing a series of
actions she planned against and will soon regret. Consider the agent
who wants to save for a decent retirement but, as each opportunity to
save approaches, prefers to spend her potential retirement
contribution on just one more trivial indulgence before finally
tightening her belt for the sake of the future satisfaction she feels
is essential to her well-being. Though this agent consistently plans
to save for her retirement, her plans can be consistently thwarted by
her discounting-induced preference reversals. Her life may thus end up
looking very different from the sort of life she wanted.



Interestingly, in addition to giving more weight to present
satisfaction than to future satisfaction, human beings also seem to
give more weight to future satisfaction than to past satisfaction.
Relatedly, human beings seem to discount past pain more than future
pain. Suppose, to appeal to a variation on Derek Parfit's famous
thought experiment (1984, 165-6), your situation is such that
either you've already suffered a perfectly safe but terribly
painful ten-hour medical procedure yesterday or else you will suffer a
perfectly safe but terribly painful nine-hour medical procedure
tomorrow. (You don't know which situation you're in
because amnesia is administered right after the procedure and
you've just woken up in the hospital confused about whether
you're recovering from the procedure or being prepped for it.)
Wouldn't you prefer to be in the former situation? Intuitively,
it seems like the prevailing and rational response would be
"most definitely!" But there is some concern that this
form of future bias, in which past rewards or costs are discounted
more than future rewards or costs, can lead to trouble (Dougherty
2011; Greene and Sullivan 2015). For example, Preston Greene and
Meghan Sullivan (2015) argue that it can be a recipe for a life of
"meager returns" and/or regret. Their reasoning is quite
elaborate, but the following simple illustration and somewhat
extemporized analysis, will hopefully provide a glimpse into some of
the interesting philosophical issues at stake. Consider Massimo, who
thoroughly enjoys massages and who can choose between a longer massage
early on or a shorter massage later. If Massimo is future biased,
then, with some variation on the length and timing of the massages, he
can easily find himself faced with the following dilemma: if he opts
for getting a longer massage early on, he will, sometime after getting
the longer massage and before the shorter massage would have been
available, regret accepting a pleasure, now past, that could have
still been in the future (even if diminished); if, alternatively, he
opts for getting a shorter massage later on (thus avoiding regret of
the preceding sort), he will face a life of "meager
returns," in which less pleasure later is, potentially
routinely, chosen over more pleasure earlier (a scenario that can
itself generate regret and/or concern, particularly once both massage
times are past, or if one recognizes, even as one is gladly awaiting a
lesser pleasure after giving up a greater pleasure that would now have
been in the past, that, insofar as the same sort of choice has arisen
repeatedly and will continue to arise repeatedly, repeated choices for
less pleasure later make for a life that is both retrospectively and
prospectively much less appealing than repeated choices for more
pleasure early on).


### 1.3 Intransitive Preferences



An agent's preference structure need not be changing over time
for it to prompt dynamic choice problems. Such problems can also be
prompted by preferences that are stable but intransitive.



One's preferences count as transitive if they satisfy the
following condition: for all *x*, *y*, and *z*,
if one prefers *x* to *y*, and *y* to *z*,
then one also prefers *x* to *z*. If one's
preferences over a set of options do not satisfy this condition, then
these preferences count as intransitive. When one's preferences
over a set of options are intransitive, then one cannot rank the
options from most preferred to least preferred. This holds even if
one's preferences over the options are complete, in the sense
that all the options are ranked with respect to one another. Suppose,
for example, that one prefers job *A* to job *B*, job
*B* to job *C*, but job *C* to job *A*. In
this case, one's complete preferences over the set {job
*A*, job *B*, job *C*} form a preference loop,
which can be represented as follows:



![job A > job B > job C > ](preference-loop1.jpg)

Figure 3.




where *x* > *y* is to be read as *x* is
preferred to *y*.



Could an agent really have intransitive preferences? Work in
experimental and theoretical economics (see, for example, Tversky
1969) suggests that intransitive preferences exist and may
be quite common. Consideration of the following situation might
help make it clear how intransitive preferences can arise (whether or
not they are rational). Suppose Jay can accept one of three jobs: job
*A* is very stimulating but low-paying; job *B* is
somewhat stimulating and pays decently; job *C* is not
stimulating but pays very well. Given this situation, one can imagine
Jay having the following preferences: He prefers job *A* over
job *B* because the difference between having a low-paying job
and a decently-paying job is not significant enough to make Jay want
to pass up a very stimulating job. Similarly, he prefers job
*B* over job *C* because the difference between having a
decently-paying job and a high-paying job is not significant enough to
make Jay want to pass up a stimulating job. But he prefers job
*C* over job *A* because the difference between having a
high-paying job and a low-paying job is significant enough to make Jay
want to pass up even a very stimulating job.



Given the famous "money pump argument," developed by
Donald Davidson, J. McKinsey, and Patrick Suppes (1955), it is clear
that intransitive preferences can be problematic. Like Dutch book
arguments regarding betting, in which the rationality of an agent is
put into question because the agent is susceptible to having a book
made against her (i.e., to accepting a series of bets which are such
that she is bound to lose more than she can gain), the money-pump
argument is concerned with agents who are vulnerable to making a
combination of choices that lead to a sure loss. According to the
money-pump argument, intransitive preferences are irrational because
they can prompt an agent to accept a series of trade offers that
leaves the agent with the same option he began with, but with less
money. Here is a case of the relevant sort. Suppose that Alex has the
following intransitive preferences: he prefers owning a computer of
type *A* to owning a computer of type *B*, owning a
computer of type *B* to owning a computer of type *C*,
and owning a computer of type *C* to owning a computer of type
*A*. Suppose also that Alex owns a computer of type *C*
and a hundred dollars in spending money. Suppose finally that, given
his preferences between different computer types, Alex prefers (i)
owning a computer of type *B* and one less dollar of spending
money over owning a computer of type *C*, (ii) owning a
computer of type *A* and one less dollar of spending money over
owning a computer of type *B*, and (iii) owning a computer of
type *C* and one less dollar of spending money over owning a
computer of type *A*. Then a series of unanticipated trade
opportunities can spell trouble for Alex. In particular, given the
opportunity to trade his current (type *C*) computer and a
dollar for a computer of type *B*, Alex's preferences
will prompt him to make the trade. Given the further opportunity to
trade his current (type *B*) computer and a dollar for a
computer of type *A*, Alex's preferences will prompt him
to trade again. And given the opportunity to trade his current (type
*A*) computer and a dollar for a computer of type *C*,
Alex's preferences will prompt him to make a third trade. But
this series of trades leaves Alex with the type of computer he started
off with and only 97 dollars. And, given that unexpected trading
opportunities may keep popping up, Alex's situation may continue
to deteriorate. Even though he values his spending money, his
preferences make him susceptible to being used as a 'money
pump.' Moreover, interesting variations on the basic money pump
argument show that an agent with intransitive preferences like those
just considered is susceptible to being money-pumped even if he shows
foresight and correctly anticipates his upcoming trading
opportunities. See, for example, Rabinowicz 2000 and Dougherty
2014.



Even if he does not serve as a money pump, an agent with intransitive
preferences can get into a great deal of trouble. To see this,
consider Warren Quinn's "puzzle of the
self-torturer" (1993): Suppose someone--who, for reasons
that will become apparent, Quinn calls the self-torturer--has a
special electric device attached to him. The device has 1001 settings:
0, 1, 2, 3, ..., 1000 and works as follows: moving up a setting
raises, by a tiny increment, the amount of electric current applied to
the self-torturer's body. The increments in current are so small
that the self-torturer cannot tell the difference between adjacent
settings. He can, however, tell the difference between settings that
are far apart. And, in fact, there are settings at which the
self-torturer would experience excruciating pain. Once a week, the
self-torturer can compare all the different settings. He must then go
back to the setting he was at and decide if he wants to move up a
setting. If he does so, he gets $10,000, but he can never permanently
return to a lower setting. Like most of us, the self-torturer would
like to increase his fortune but also cares about feeling well. Since
the self-torturer cannot feel any difference in comfort between
adjacent settings but gets $10,000 at each advance, he prefers, for
any two consecutive settings *s* and *s*+1, stopping at
*s*+1 to stopping at *s*. But, since he does not want to
live in excruciating pain, even for a great fortune, he also prefers
stopping at a low setting, such as 0, over stopping at a high setting,
such as 1000.



Given his preferences, the self-torturer cannot rank the setting
options he faces from most preferred to least preferred. More
specifically, his preferences incorporate the following preference
loop:



![setting 0 < setting 1 < ... < setting 999 < setting 1000 < setting 0](preference-loop2.jpg)

Figure 4.




Relatedly, the self-torturer's preferences over the available
setting options are intransitive. If his preferences were transitive,
then, given that he prefers setting 2 to setting 1 and setting 1 to
setting 0, he would prefer setting 2 to setting 0. Given that he also
prefers setting 3 to setting 2, he would (assuming transitivity)
prefer setting 3 to setting 0. Given that he also prefers setting 4 to
setting 3, he would (assuming transitivity) prefer setting 4 to
setting 0. Continuing with this line of reasoning leads to the
conclusion that he would, if his preferences were transitive, prefer
setting 1000 to setting 0. Since he does not prefer setting 1000 to
setting 0, his preferences are intransitive. And this intransitivity
can lead the self-torturer down a terrible path. In particular, if,
each week, the self-torturer follows his preference over the pair of
settings he must choose between, he will end up in a situation that he
finds completely unacceptable. This is quite disturbing, particularly
once one realizes that, although the situation of the self-torturer is
pure science fiction, the self-torturer is not really alone in his
predicament. As Quinn stresses, "most of us are like him in one
way or another. [For example, most of us] like to eat but also care
about our appearance. Just one more bite will give us pleasure and
won't make us look fatter; but very many bites will"
(Quinn 1993, 199).



Given the money pump argument and the puzzle of the self-torturer, we
can, it seems, conclude that although intransitive preferences are
sometimes understandable, acting on them can be far from sensible.
(Note, however, that, as Duncan MacIntosh (2010) suggests, the notion
of "an unacceptable situation" plays an important role
here and the question of how to cash out this notion stands in need of
additional attention. For a recent attempt at addressing this issue,
see (Andreou 2015), wherein instrumental rationality is portrayed as
accountable to "subjective appraisal responses" that go
beyond the agent's preferences and that sometimes allow some
outcomes in a "preference loop" to figure as (rationally)
acceptable and others to figure as (rationally) unacceptable.)


### 1.4 Vague Goals and other Challenging Wholes



Like intransitive preferences, vague goals or projects can prompt
dynamic choice problems even if the agent's preference structure
is not changing over time. Indeed, some have suggested that the deep
source of the self-torturer's problem, and what prompts his
intransitive preferences, is that his goal of avoiding extreme pain is
vague in the sense that, in the situation described, avoiding extreme
pain requires engaging in a multitude of goal-directed actions that
are not individually necessary or sufficient for the achievement of
the goal and that are thus dispensable and perhaps even dominated if
considered individually (Tenenbaum and Raffman, 2012). It may be
helpful to consider a more familiar example of a vague goal or
project, such as that of writing a good book. As Sergio Tenenbaum and
Diana Raffman explain, this project may be characterizable as follows
(2012, 99-100):


1. Its completion requires the successful execution of many momentary
actions.
2. For each momentary action in which you execute the project,
failure to execute that action would not have prevented you from
writing the book.
3. On many occasions when you execute the project, there is something
else that you would prefer to be doing, given how unlikely it is that
executing the project at this time would make a difference to the
success of your writing the book.
4. Had you failed to execute the project every time you would have
preferred to be doing something else, you would not have written the
book.
5. You prefer executing the project at every momentary choice
situation in which you could work on the project, over not writing the
book at all.



It is not difficult to see how, in a case like this, seemingly
rational "local" decisions can lead one off course.



Tenenbaum and Raffman's discussion of the pursuit of vague goals
is interestingly related to Luca Ferrero's suggestion that many
activities are "made up of momentary actions that relate in
non-local ways that span over the entire length of the
activities" and "require the agent's continuous
appreciation of the structure and outcome of the extended activities
taken as a whole" (2009, 406). Ferrero focuses on activities
that have a narrative dimension, in that "the unfolding of the
characteristic temporal structure of ...[the] activities can be
fully and perspicuously described solely by a narrative"
(412-3), but the pursuit of vague goals also seems to fit
Ferrero's initial description, as well as his idea that
activities of the relevant sort involve the "paradigmatic
operation" of the "diachronic will" (406). In all
such activities, relentless guidance by "proximal
concerns" interferes with what is required by "the
activity's global structure" (406).


### 1.5 Autonomous Benefit Cases



The discussions in the preceding three sections suggest that, when it
comes to serving one's concerns well, the ability to choose
counter-preferentially may be quite helpful. This point is reinforced
by the possibility of autonomous benefit cases.



In autonomous benefit cases, one benefits from forming a certain
intention but not from carrying out the associated action. The
autonomous benefit cases that have figured most prominently in the
literature on dynamic choice are those in which carrying out the
action associated with the beneficial intention is detrimental rather
than just unrewarding. Among the most famous autonomous benefit cases
is Gregory Kavka's "toxin puzzle" (1983). In
Kavka's invented case,



> 
> an eccentric billionaire...places before you a vial of
> toxin...[and provides you with the following information:] If you
> drink [the toxin], [it] will make you painfully ill for a day, but
> will not threaten your life or have any lasting effects.... The
> billionaire will pay you one million dollars tomorrow morning if, at
> midnight tonight, you intend to drink the toxin tomorrow
> afternoon.... You need not drink the toxin to receive the money;
> in fact, the money will already be in your bank account hours before
> the time for drinking it arrives, if you succeed.... [The]
> arrangement of...external incentives is ruled out, as are such
> alternative gimmicks as hiring a hypnotist to implant the
> intention... (Kavka 1983, 33-4)
> 



Part of what is interesting about this case is that, even though most
people would gladly drink the toxin for a million dollars, getting the
million dollars is not that easy. This is because one does not get the
million dollars for drinking the toxin. Indeed, one does not get
anything but a day of illness for drinking the toxin. As Kavka
explains, by the time the toxin is to be consumed, one either already
has the million in one's account or not; and drinking the toxin
will not get one any (additional) funds. Assuming one has no desire to
be ill for nothing, drinking the toxin seems to involve acting
counter-preferentially--and this is, if not impossible, at least
no easy feat. So, given a clear understanding of the situation, one is
likely to find it difficult, if not impossible, to form the intention
to drink the toxin. Presumably, one cannot form the intention to drink
the toxin if one is confident that one will not drink it. If only one
could somehow rely on the cooperation of one's future self, one
could then genuinely form the intention to drink the toxin and thus
get the million--a wonderful result from the perspective of both
one's current and one's future self. But, alas,
one's future self will, it seems, have no reason to drink the
toxin when the time for doing so arrives.



Here again we have a situation in which doing well by oneself is not
easy.


## 2. Solving Dynamic Choice Problems



Given how much trouble dynamic choice problems can cause, it is
natural to wonder whether and how they can be solved. Various
solutions of varying scope have been proposed in the literature on
dynamic choice. The first three subsections that follow focus on ideas
regarding the practical issue of dealing with dynamic choice problems.
The fourth subsection focuses on attempts at resolving the theoretical
puzzles concerning rational choice raised by various dynamic choice
problems.


### 2.1 Rational Irrationality



Two strategies that we can sometimes use to solve (in the sense of
practically deal with) dynamic choice problems are suggested in
Kavka's description of the toxin puzzle. One strategy is to use
gimmicks that cause one to reason or choose in a way that does not
accord with one's preferences. The other strategy involves the
arrangement of external incentives. Although such maneuvers are ruled
out in Kavka's case, they can prove useful in less restrictive
cases. This subsection considers the former strategy and the next
subsection considers the latter strategy.



If one accepts the common assumption that causing oneself to reason or
choose in a way that does not accord with one's preferences
involves rendering oneself irrational, the former strategy can be
thought of as aiming at rationally-induced irrationality. A fanciful
but clear illustration of this strategy is presented in Derek
Parfit's work (1984). In Parfit's example (which is
labeled *Schelling's Answer to Armed Robbery* because it
draws on Thomas Schelling's view that "it is not a
universal advantage in situations of conflict to be inalienably and
manifestly rational in decision and motivation" (Schelling 1960,
18)), a robber breaks into someone's house and orders the owner,
call him Moe, to open the safe in which he hoards his gold. The robber
threatens to shoot Moe's children unless Moe complies. But Moe
realizes that both he and his children will probably be shot even if
he complies, since the robber will want to get rid of them so that
they cannot record his getaway car information and get it to the
police (who will be arriving from the nearest town in about 15 minutes
in response to Moe's call, which was prompted by the first signs
of the break-in). Fortunately, Moe has a special drug at hand that, if
consumed, causes one to be irrational for a brief period. Recognizing
that this drug is his only real hope, Moe consumes the drug and
immediately loses his wits. He begins "reeling about the
room" saying things like "Go ahead. I love my children. So
please kill them" (Parfit 1984, 13). Given Moe's current
state, the robber cannot do anything that will induce Moe to open the
safe. There is no point in killing Moe or his children. The only
sensible thing to do now is to hurry off before the police arrive.



Given that consuming irrationality drugs and even hiring hypnotists
are normally not feasible solutions to our dynamic choice problems,
the possibility of rationally inducing irrationality may seem
practically irrelevant. But it may be that we often benefit from the
non-conscious employment of what is more or less a version of this
strategy. We sometimes, for example, engage in self-deception or
indulge irrational fears or superstitions when it is convenient to do
so. Many of us might, in toxin-type cases, be naturally prone to dwell
on and indulge superstitious fears, like the fear that one will
somehow be jinxed if one manages to get the million dollars but then
does not drink the toxin. Given this fear, one might be quite
confident that one will drink the toxin if one gets the million; and
so it might be quite easy for one to form the intention to drink the
toxin. Although this is not a solution to the toxin puzzle that one
can consciously plan on using (nor is it one that resolves the
theoretical issues raised by the case), it may nonetheless often help
us effectively cope with toxin-type cases. (For a clear and compact
discussion concerning self-deception, "motivationally biased
belief," and "motivated irrationality" more
generally, see, for example, Mele 2004.)


### 2.2 The Arrangement of External Incentives



The other above-mentioned strategy that is often useful for dealing
with certain dynamic choice problems is the arrangement of external
incentives that make it worthwhile for one's future self to
cooperate with one's current plans. This strategy can be
particularly useful in dealing with discounting-induced preference
reversals. Consider again the agent who wants to save for a decent
retirement but, as each opportunity to save approaches, prefers to
spend her potential retirement contribution on just one more trivial
indulgence before finally tightening her belt for the sake of the
future satisfaction she feels is essential to her well-being. If this
agent's plans are consistently thwarted by her
discounting-induced preference reversals, she might come to the
conclusion that she will never manage to save for a decent retirement
if she doesn't supplement her plans with incentives that will
prevent the preference reversals that are causing her so much trouble.
If she is lucky, she may find an existing precommitment device that
she can take advantage of. Suppose, for example, that she can sign up
for a program at work that, starting in a month, automatically
deposits a portion of her pay into a retirement fund. If she cannot
remove deposited funds without a significant penalty, and if she must
provide a month's notice to discontinue her participation in the
program, signing up for the program might change the cost-and-reward
structure of spending her potential retirement contributions on
trivial indulgences enough to make this option consistently
dispreferred. If no ready-made precommitment device is available, she
might be able to create a suitable one herself. If, for example, she
is highly averse to breaking promises, she might be able to solve her
problem by simply promising a concerned friend that she will
henceforth deposit a certain percentage of her pay into a retirement
fund.



In some cases, one might not be confident that one can arrange for
external incentives that will get one's future self to
voluntarily cooperate with one's current plans. One might
therefore favor the related but more extreme strategy of making sure
that one's future self does not have the power to thwart
one's current plans. Rather than simply making cooperation more
worthwhile (and thus, in a sense, more compelling), this strategy
involves arranging for the use of force (which *compels* in a
stronger sense of the term). A fictional but particularly famous
employment of the strategy (which is discussed in, for example, Elster
1984) is its employment by Odysseus in Homer's *Odyssey*.
Because he longed to hear the enchanting singing of the Sirens, but
feared that he would thereby be lured into danger, Odysseus instructed
his companions to tie him to the mast of his ship and to resist his
(anticipated) attempts at freeing himself from the requested
bonds.


### 2.3 Symbolic Utility



Another strategy for dealing with certain dynamic choice
problems--this one proposed by Robert Nozick (1993)--is the
strategy of investing actions with symbolic utility (or value) and
then allowing oneself to be influenced not only by the causal
significance of one's actions, but also by their symbolic
significance. According to Nozick, "actions and outcomes can
symbolize still further events ... [and] draw upon themselves the
emotional meaning (and utility...) of these other events"
(26). If "we impute to actions... utilities coordinate with
what they symbolize, and we strive to realize (or avoid) them as we
would strive for what they stand for" (32), our choices will
differ from what they would be if we considered only the causal
significance of our actions. Consider, for example, the case of the
self-torturer. Suppose the self-torturer has moved up ten settings in
ten weeks. He is still in a very comfortable range, but he is starting
to worry about ending up at a high setting that would leave him in
excruciating pain. It occurs to him that he should quit while he is
ahead, and he begins to symbolically associate moving up a setting at
the next opportunity with moving up a setting at every upcoming
opportunity. By the time the next opportunity to move up a setting
comes around, the extremely negative symbolic significance of this
potential action steers him away from performing the action. For a
structurally similar but more down-to-earth example, consider someone
who loves overeating but is averse to becoming overweight. If this
individual comes to symbolically associate having an extra helping
with overeating in general and thus with becoming overweight, he may
be averse to having the extra helping, even if, in causal terms, what
he does in this particular case is negligible.


### 2.4 Plans and Resoluteness



The three strategies discussed so far suggest that, to cope with
dynamic choice problems, one must either mess with one's
rationality or else somehow change the payoffs associated with the
options one will face. Some philosophers--including, for example,
Michael Bratman (1999; 2006), David Gauthier (1986; 1994), and Edward
McClennen (1990; 1997)--have, however, suggested that the
rational agent will not need to resort to such gimmicks as often as
one might think--a good thing, since making the necessary
arrangements can require a heavy investment of time, energy, and/or
money. The key to their arguments is the idea that adopting plans can
affect what it is rational for one to do even when the plans do not
affect the payoffs associated with the options one will face;
relatedly, their arguments incorporate the idea that rationality at
least sometimes calls for resolutely sticking to a plan even if the
plan disallows an action that would fit as well or better with
one's preferences than the action required by the plan. (For
some interesting discussion relating resoluteness, one's current
options, and the options one will face, see Portmore 2019.) For
Bratman, Gauthier, and McClennen, being resolute is not simply useful
in coping with dynamic choice problems. Rather, it figures as part of
a conception of rationality that resolves the theoretical puzzles
concerning rationality and choice over time posed by various dynamic
choice problems. In particular, it figures as part of a conception of
rationality whose dictates provide intuitively sensible guidance not
only in simple situations but also in challenging dynamic choice
situations. (Significantly, in some of his more recent work, Bratman
(2014; 2018) distances himself from the idea that rational
resoluteness involves acting contrary to one's current
preferences by suggesting that when rationality calls for sticking to
a plan even if this is not called for by one's current
preferences, there may be "rational pressure" to change
one's current preferences.)



We are, as Michael Bratman (1983; 1987) stresses, planning creatures.
Our reasoning is structured by our plans, which enable us to achieve
complex personal and social goals. To benefit from planning, one must
take plans seriously. For Bratman, this involves, among other things,
(i) recognizing a general rational pressure favoring sticking to
one's plan so long as there is no problem with the plan (Bratman
2006, section 8), and (ii) "taking seriously how one will see
matters at the conclusion of one's plan, or at appropriate
stages along the way, in the case of plans or policies that are
ongoing" (1999, 86). In accordance with these proposed
requirements, Bratman (1999) concludes that rationality at least
sometimes calls for sticking to a plan even if this is not called for
by one's current preferences. Moreover, although this conception
of rationality requires that one sometimes resist one's current
preferences, it is taken to prompt more sensible choices in
challenging dynamic choice situations than do conceptions of
rationality whose dictates do not take plans seriously.



The significance of the first requirement is easy to see. If there is
a general rational pressure favoring sticking to one's plan so
long as there is no problem with it, then a rational agent that takes
plans seriously will not get into the sort of trouble Broome imagines
Abraham might get into. When faced with incommensurable alternatives,
the rational agent who takes plans seriously will adopt a plan and
then stick to it even if his preferences are consistent with pursuing
an alternative course of action.



What about the significance of the second requirement? For Bratman, if
one is concerned about how one will see matters at the conclusion of
one's plan or at appropriate stages along the way, then one
will, other things equal, avoid adjusting one's plan in ways
that one will regret in the future. So Bratman's planning
conception of rationality includes a "no-regret
condition." And, according to Bratman, given this condition, his
conception of rationality gives intuitively plausible guidance in
cases of temptation like the case of the self-torturer or the
retirement contribution case. In particular, it implies that, in such
cases, the rational planner will adopt a plan and refrain from
adjusting it. For in both sorts of cases, if the simple fact that
one's preferences favor adjusting one's plan leads one to
adjust it, one is bound to end up, via repeated adjustments of
one's plan, in the situation one finds unacceptable. One is thus
bound to experience future regret. And, while Bratman allows that
regret can sometimes be misguided--which is why he does not
present avoiding regret as an exceptionless imperative--there are
not, for Bratman, any special considerations that would make regret
misguided if one gave into temptation in cases like the case of the
self-torturer or the retirement contribution case.



Based on their own reasoning concerning rational resoluteness,
Gauthier (1994) and McClennen (1990; 1997) argue that rational
resoluteness can help an agent do well in autonomous benefit cases
like the toxin case. They maintain that being rational is not a matter
of always choosing the action that best serves one's concerns.
Rather it is a matter of acting in accordance with the deliberative
procedure that best serves one's concerns. Now it might seem as
though the deliberative procedure that best serves one's
concerns must be the deliberative procedure that calls for always
choosing the action that best serves one's concerns. But
autonomous benefit cases like the toxin case suggest that this is not
quite right. For, the deliberative procedure that calls for always
choosing the action that best serves one's concerns does not
serve one's concerns well in autonomous benefit cases. More
specifically, someone who reasons in accordance with this deliberative
procedure does worse in autonomous benefit cases than someone who is
willing to resolutely stick to a prior plan that he did well to adopt.
Accordingly, Gauthier and McClennen deny that the best deliberative
procedure requires one to always choose the action that best serves
one's concerns; in their view, the best deliberative procedure
requires some resoluteness. Relatedly, they see drinking the toxin in
accordance with a prior plan to drink the toxin as rational, indeed as
rationally required, given that one did well to adopt the plan; so
rationality helps one benefit, rather than hindering one from
benefiting, in autonomous benefit cases like the toxin case.



Note that, while there is widespread agreement that a plausible
conception of rationality will imply that the self-torturer should
resist the temptation to keep advancing one more setting, there is no
widespread agreement that a plausible conception of rationality will
imply that it is rational to drink the toxin. For those who find the
idea that it is rational to drink the toxin completely
counter-intuitive, its emergence figures as a problematic, rather than
welcome, implication of Gauthier's and McClennen's views
concerning rational resoluteness.



If Bratman and/or Gauthier and McClennen are on the right
track--and this is, of course, a big if--then (some form of)
resoluteness may often be the key to keeping oneself out of potential
dynamic choice traps. It may also be the key to resolving various
puzzles concerning rationality and dynamic choice.



In an interesting critique of planning solutions to cases of
temptation, Tenenbaum and Raffman (2012) challenge the purported
centrality of resoluteness. They suggest that, in cases of temptation,
instrumental rationality may not require planning and resoluteness,
but simply exercising "sufficiently many"
"permissions" to do something other than what "would
be best at a given moment" when this is required by a
"rationally innocent" goal or project. For instance,
"suppose you take a break from writing an important memo and
start surfing the web. Surely surfing for one additional second will
not prevent you from completing the memo, but if you surf for long
enough you won't have time to finish it" (110).
Instrumental rationality requires that you stop surfing at an
acceptable point. But this need not involve stopping at a point
determined by a prior plan. Whether or not you have a plan to stop at
time t, and whether or not you resolutely adhere to such a plan need
not be of crucial importance. What matters is that, ultimately, you
stop in good time by exercising, at one or more points, the rational
permission to do something other than what would be best at that
moment with an eye to achieving the rationally innocent goal of
completing the important memo. Tenenbaum (forthcoming) develops a
theory of instrumental rationality that illuminates and accommodates
the need to exercise rational permissions of the sort just
described.


## 3. Some Familiar Phenomena Illuminated by Dynamic Choice Theory



Although dynamic choice problems are often presented with the help of
fanciful thought experiments, their interest is not strictly
theoretical. As this section highlights, they can wreak havoc in our
real lives, supporting phenomena such as self-destructive addictive
behavior and dangerous environmental destruction. In some cases, these
phenomena can be understood in terms of procrastination (Andreou
2007), which seems to be, by its very nature, a dynamic choice problem
(Stroud 2010).



According to the most familiar model of self-destructive addictive
behavior, such behavior results from cravings that limit "the
scope for volitional control of behavior" and can in some cases
be irresistible, "overwhelm[ing] decision making
altogether" (Loewenstein 1999, 235-6). But, as we know
from dynamic choice theory, self-destructive behavior need not be
compelled. It can also be supported by challenging choice situations
and problematic preference structures that prompt dynamic choice
problems. Reflection on this point has led to new ideas concerning
possible sources of self-destructive addictive behavior. For example,
George Ainslie (2001) has developed the view that addictive habits
such as smoking--which can, it seems, flourish even in the
absence of irresistible craving--are often supported by
discounting-induced preference reversals. Given the possibility of
discounting-induced preference reversals, even someone who cares
deeply about having a healthy future, and who therefore does not want
to be a heavy smoker, can easily find herself smoking cigarette after
cigarette, where this figures as a series of indulgences that she
plans against and then regrets.



Reflection on dynamic choice theory has also led to new ideas in
environmental philosophy. For example, Chrisoula Andreou (2006) argues
that, although dangerous environmental destruction is usually analyzed
as resulting from interpersonal conflicts of interest, such
destruction can flourish even in the absence of such conflicts. In
particular, where individually negligible effects are involved, as is
the case among "creeping environmental problems" such as
pollution, "an agent, whether it be an individual or a
*unified* collective, can be led down a course of destruction
simply as a result of following its informed and perfectly
understandable but *intransitive* preferences" (Andreou
2006, 96). Notice, for example, that if a unified collective values a
healthy community, but also values luxuries whose production or use
promotes a carcinogenic environment, it can find itself in a situation
that is structurally similar to the situation of the self-torturer.
Like the self-torturer, such a collective must cope with the fact that
while one more day, and perhaps even one more month of indulgence can
provide great rewards without bringing about any significant
alterations in (physical or psychic) health, "sustained
indulgence is far from innocuous" (Andreou 2006, 101).



Clearly, success in achieving a long-term goal can require showing
some restraint along the way; but it is tempting to put off showing
restraint and to favor a bit more indulgence over embarking on the
challenging doings or omissions that will serve the valued long-term
goal. Here, as in many other contexts, procrastination figures as a
serious threat.



Though both philosophically intriguing and practically significant,
procrastination has only recently received substantial attention as an
important topic of philosophical debate. (Much of the debate can be
found in a collection of papers on the topic edited by Chrisoula
Andreou and Mark D. White (2010).) It has perhaps been assumed that
procrastination is just a form of weakness of will and so, although
there has been little explicit discussion of procrastination, most of
the philosophical work necessary for understanding procrastination has
already been done. But, as Sarah Stroud has argued (2010), this
assumption is problematic, since there are cases of procrastination
that do not fit with the traditional conception of weakness of will,
which casts the agent as acting against her better judgment, or with
the influential revisionary conception of weakness of will due to
Richard Holton (1999), which casts the agent as acting irresolutely.
Although the well-developed literature on weakness of will is an
important resource in the study of procrastination, there is a lot
more philosophical work that needs to be done, and the modeling work
that seems to be most promising focuses heavily on the fact that
procrastination is a problem faced by agents whose choices are spread
out over time.


## 4. Concluding Remarks



When one performs a series of actions that do not serve one's
concerns well, it is natural to feel regret and frustration. Why, it
might be wondered, is one doing so badly by oneself? Self-loathing,
compulsion, or simple ignorance might in some cases explain the
situation; but, oftentimes, none of these things seems to be at the
root of the problem. For, in many cases, one's steps along a
disadvantageous course seem voluntary, motivated by the prospect of
some benefit, and performed in light of a correct understanding of the
consequences of each step taken. As we have seen, dynamic choice
theory makes it clear how such cases are possible.



Although an agent with a dynamic choice problem can often be described
as insufficiently resolute, she is normally guided by her preferences
or her evaluation of the options she faces. As such, she is not, in
general, properly described as simply out of control. Still, the
control she exhibits is inadequate with respect to the task of
effectively governing her (temporally-extended) self. So her problem
is, at least in part, a problem of effective self-governance over
time. Accordingly, some work on choice over time (e.g. Velleman 2000;
Bratman, 2012) includes discussion of effective self-governance over
time and explores the connection between the requirements for
effective self-governance over time and the requirements for rational
choice over time (sometimes referred to as the requirements of
diachronic rationality). Some big questions in this area include the
following: To what extent does self-governance over time (or at least
effective self-governance over time) require cross-temporal coherence
in the form of a presumption in favor of prior intentions? To what
extent does diachronic rationality require self-governance over time?
And to what extent does diachronic rationality require cross-temporal
coherence in the form of a presumption in favor of prior intentions.
My own view is that it is ensuring the avoidance of self-defeating
behavior rather than ensuring self-governance over time that is
rationally required, and so diachronic rationality requires a
presumption in favor of prior intentions only when this is necessary
for avoiding self-defeating behavior (Andreou, 2012). But debate on
this topic has not been very extensive and further exploration of the
topic is certainly in order.