Why zero temporal discounting *within* a life is less plausible than across generations

For an individual there is both cardinal Benthamite utilitarianism (“utils”) and preference utilitarianism.  The two sometimes conflict (would you take a pill that gave you joy when you saw suffering?), and a plausible consequentialist theory attaches some weight to both.

Most of the arguments for zero discounting of utility apply to the cardinal measure.  Don’t put off going to the dentist just because you don’t like pain — when the pain finally arrives, it will be no less real.

But now shift your attention to the preference utilitarianism.  Let’s say a person had a strong preference that “the Knicks win an NBA title in 2022,” deciding that it isn’t nearly good enough for the Knicks to win that title in 2030.  That is a kind of positive time preference.  Arguably it is ungrounded and irrational, but that isn’t quite grounds for dismissing it.  Preference utilitarianism simply counts the preference and whether it is satisfied.  You might as well argue it is irrational to care about the Knicks in the first place, never mind 2022 vs. 2030.  And indeed it is, just like so many other of our preferences do not really admit of defense or justification in external terms.

And thus, through the medium of preference satisfaction utilitarianism, we cannot altogether dismiss positive time preference for the individual.

When considering trade-offs of utilities across the generations, there are Benthamite comparisons but there is no meaningful preference utilitarianism, since there are different persons at stake.  That leaves us with one fewer argument for positive time preference in the intergenerational case.


I've got mine, you are on your own?

Sounds defensible, even when taking small steps towards a much better world.

A pill that "... that gave you enjoy when you saw suffering?" Whatever that means, I'm sticking with deontology. More so than ever, perhaps.

I assume he meant joy, but maybe it’s a Straussian misspelling.

"[W]ould you take a pill that gave you joy(sp) when you saw suffering?" Many thoughtful atheists don't believe in God because bad things, very bad things, happen to good people. If God is all powerful, why would He do such a thing? Of course, that question has confounded humanity from the beginning of time. The explanation in the Jewish Bible (Old Testament) is sin: all of God's chosen are punished for the sins of the few. That's not a very satisfying answer. If I am to be punished for the sins of others, why should I try to lead a good life by doing good works? The explanation in the Christian Bible (New Testament) is not to worry about suffering in this (short) life because time will soon come to an end and paradise awaits good, faithful people. That's not a very satisfying answer either given that good, faithful people have been waiting and suffering over 2,000 years for paradise that was supposed to be imminent. The explanation of the humanist is that suffering by good people offers the opportunity for good works, which provide their own reward. Maybe Cowen can explain how an economist would place a value on these three explanations for suffering by applying the discounting technique.

Or we could tie it to the concrete suggestion that the US should stop accepting any refugees. A good moment for that pill, perhaps.

A rational discussion presuming the supernatural. I doubt it. Although, I do believe there have been published research showing religious belief has (economic) value. (Mental health, crowd control, social networks, etc.) But I couldn't point to any - not that I'd care to jump down that rabbit hole.

Your take on the religious explanations are lacking a very important element—the after life and the idea that your reward awaits you in the next life based on how you lived during mortality. Sure, the first apostles anticipated Christ’s second coming to be eminent. But the real paradise they awaited was in the after life. You can criticize that belief, but it’s an essential component. Another related view is that this life is a test and opportunity to learn and grow. Easy tests do not discriminate well or incentivize growth. People need trials and hardships. On top of this you can throw in the belief that people have agency and so we’re affected by others’ choices and this is part of the test as well

Of course a positive time preference makes sense within an individual life. Neither our preferences nor opportunities are stable.

And you might die before the Knicks win in 2030, having missed out on eight years of happy memories about the time they would have won in 2022. Actually, all of us might die before the Knicks win again.

"Actually, all of us might die before the Knicks win again."

I had a grandfather who lived his whole life around Chicago and made it almost to 100 without ever seeing the Cubs win the Series. A level of futility that did, at least, result in one of the greatest songs about baseball (that hardly anybody knows).

This. Preferences change a lot and often not in a way that can be foreseen. Is reading Harry Potter going to deliver the same utility at 39 that it does at 9? I don't think a 9-year old can make that calculation.

Utilitarian preferences do not span generations? What nonsense. A great many political and social preferences are highly heritable and long-lived. That's why it's so hard to get rid of the bad ones.

Not really. I'm reading a book on the Vanderbilts by one of their descendants that shows while they were once the world's wealthiest family ($10B, before JDR), by four generations none of them were even a mere millionaire by 1971. Then again, The Commodore himself was rather ruthless and did not care that much about his biological offspring, as he had very high standards and did not give his offspring that much while he was alive, and after he died it seems they did not have good business sense.

The original passage by TC reminds me of some SAT reading comprehension test designed to trip up the majority of people, as it's hard to figure out what the author is trying to say without a specialist knowledge of the subject. Possibly the root of the passage is dealing with how discount rates are not accurate over long time horizons, the $24 in beads in exchange for Manhattan island problem (a good deal for the Native Americans, if they had a compound passbook savings account with Chase Manhattan bank)

Ok, in reading the prior post after puzzling over this one, I realize "business hates families" because short term, single people can work long hours, then spend all they earn buying consumption goods from businesses.

On the other hand, families produce non-workers who need lots of taxes for the long term to turn them into workers businesses will want to hire in 25 years. The families will cease excess consumption and invest in savings or capital, like saving for college, or saving for buying a house, which businesses opposing taxes mean old houses, because no taxes are available to build access to the vast vacant land inland from navigable waters. Bidding up prices on old houses forcing their single peers to move back in with parents or with friends limiting consumption to imported techie toys. Where lack of transport is really bad, single people find ways to live near work and don't buy cars, nor expensive bikes which just get stolen, using instead imported bikes, scooters, or Uber, etc.

The short term focus of business on profit by driving single consumption lifestyle without kids and low taxes making having a family really really hard, other than single moms in poor school districts while she works long irregular hours so her kids are poorly educated, unfocused, undisciplined, and probably not at good self learning. Thus poor fuuture workers, thus low earners, and poor customers.

So, why do so many economists want so many poor consumers who will be vvery undesirable to businesses?

After all, economists teach a lot of what is in MBA programs, and since circa 1980, MBAs have been taught to hate families.

This may be one fewer argument for intergenerational preferences but that still doesn’t mean we can ignore discount rates.

Suppose I can take one of two actions today: Action A will save people living 100 years from now $1 trillion. Action B will save people living 200 years from now $2 trillion. Tyler’s argument suggests that I should pick Action B. I have no reason to prefer people living 100 or 200 years in the future—I have no idea who they will be—and so I may as well do the thing that creates the biggest good.

But that can’t be right. Economies may grow and so giving people alive 100 years from now an extra $1 trillion may result in more than an extra $2 trillion in 200 years. Growth also means that people in 2219 will be richer than the people in 2119 and the MU of the extra $1 trillion in 100 years may be more than the MU of an extra $2 trillion in 200 years.

I'm not sure Tyler's got this one worked out right.

In my view the measure of hedons and dolors is best understood via the Macro:

Human history can be sped up or slowed down. Speeding it up reduces total dolors and increases total hedons.

The sooner that countries become more like Texas (the best state) the better off humans are. Property rights. Rule of law. Minimal govt. Right to work. These are the directional flow towards Civilization.

Technology follows this same Macro. Meaning we can posit an alt.universe where Ma Bell was not allowed to be a monopoly and we had the commercial Internet 20 years earlier.

In the March of History analysis is not irrational to want X sooner, bc Y,Z,,AA come faster - perhaps faster still, we are either increasing thrust, decreasing thrust, it's not just forward or reverse.

Total aggregate hedons/dolors or hedons/dolors per capita?

Mortality rates are > 0 for every age so it's not irrational to have a preference for the Knicks to win the championship earlier than later (or for internal discount rates to be positive more generally).

All is hopeless when you understand Behavioral Economics.

Pick whatever model you like as a rational econ.

Procrastination, status quo bias, and overconfidence rule.

Groups can have preferences, or at least that's the basis for relativist moral positions. I'm not sure that kind of temporal preference utilitarianism is coherent. If we ignore the trivial cases where the more distant preference actually fails to happen (like the Knicks go out of business before 2030) is it really consistent to have a time preference? If the utils are "guaranteed", then I don't think it is logically coherent to prefer them in a nearer time. You could argue that when you are older your ability to enjoy the moment will be less, but to me that's fewer utils, not the same utils further away. The fact that the preference is irrational really does matter, because you could equally have an preference for more distant events --- to have longer to look forward to it, for example. When I was a kid I'd sometimes eat my greens first just to not have 'em hanging over the rest of the meal.

We do not know how many future generations will exist (asteroid etc). The sun has an expiration date.

Zero temporal discounting is always implausible. Very small temporal discounting is always implausible.

If it were plausible, then we would be devoting substantial resources today toward finding a new planet for when our sun becomes a red giant. I can't even begin to imagine what we'd have to spend to survive the collision of the Milky Way with Andromeda.

At the very least, we would be planning intermediate steps.

Preference utilitarianism is incoherent. Some entities will always have incompatible preferences with some other entities, and be uncompromising about it. You can't define a non-arbitrary numerical trade-off between uncompromisingly incompatible preferences. You can't ignore them either, as these entities are part of the world. This is why you can't make "the world a better place" in a preference-utilitarian sense. Someone will always have a preference that disagrees with your calculus, uncompromisingly so, which makes it incoherent. In addition to this problem, preference utilitarianism suffers from the same tiling problems as hedonistic utilitarianism: You could invent cost-effective minds who have only very simple preferences, such as an arbitrary counter being set at a specific number, and then set that counter to that number. This would be the optimal solution to preference utilitarianism, even if it were coherent, and it's no more attractive to psychonormal people than hedonium or paperclip-maximization.

But none of that should matter because there's no good, non-arbitrary reason to be a utilitarian to begin with. The utility of others is not my utility, so why should I treat it as such? Why even factor it in? Even if you have other-regarding preferences, those preferences are usually not strictly utilitarian for psychonormal people, so why have discussions that pre-suppose that we ought to be utilitarians?

For me, time discounting is easy to explain: I discount because of increasing uncertainty over time, including death probability.

I don’t see why we even need to move to the generational level. Why not just say there is no meaningful preference utilitarianism across individuals, period? That rules out positive time preference, even within a generation, so long as we are talking about multiple people.

What books would you suggest for someone new to discounting.

Mercatus put out a symposium on the social discount rate. That's a good place to start for a brief overview of the main issues involved. The essays include citations to the most important literature.


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