alt.hn

4/10/2026 at 1:38:39 PM

The effects of caffeine consumption do not decay with a ~5 hour half-life

 https://www.lesswrong.com/posts/vefsxkGWkEMmDcZ7v/the-effects-of-caffeine-consumption-do-not-decay-with-a-5

by swah

4/10/2026 at 3:14:29 PM

I take pentoxyfylline (a synthetic substituted xanthine, caffeine is a natural substituted xanthine) occasionally as a nootropic and supplement for vascular health and anecdotally for me it has several nice caffeine like properties without the jitters/ long tail, sleep effects etc.

I find the listed side effects don’t happen for me besides occasional flush/blush. Which at my age is more like youthful vigor.

Caffeine is is 1,3,7-trimethylxanthine, pentoxyfylline is 3,7-dimethyl-1-(5-oxohexyl)xanthine.

Good effects are: sustained mental clarity, focus and energy with a smoother more stable baseline than caffeine’s bursty performance; good sleep, but strangely you can also stay up, if you prefer; feeling similar to “after exercise”. Half life is listed as under 1 hour, but beneficial effects can be felt for half a day after 400mg (a standard dose). So maybe there’s something like metabolite dynamics occurring here too.

This ends my erowid/hive style “trip/nootropic” report ;)

by keepamovin

4/10/2026 at 3:28:27 PM

You should start a xanthina where you serve various xanthinated beverages.

by ronjakoi

4/11/2026 at 4:09:20 AM

Coukd call it... xanzi-bar

by CableNinja

4/10/2026 at 7:01:10 PM

Do you know how much it affects your deep sleep duration?

People who drink caffeine at night may claim to be able to sleep still, but they will find that deep sleep stages are shorter, which is significant because it may be the most important type of sleep.

by quinncom

4/10/2026 at 8:11:08 PM

I never slept as bad in my life as when I had a single can of coca cola at 8-9 pm and went to bed at 11-12pm

I did this for a while working nights until I caught on. The nights I didn't have a can were much better.

by bot403

4/10/2026 at 6:03:02 PM

Pentoxyfylline is prescription in the USA?

by qingcharles

4/10/2026 at 1:59:13 PM

I think it is already pretty widely recognized that caffeine can disrupt sleep taken even as early as 6 or 7 hours before bed. I usually don't drink coffee or caffeinated tea after 12 for this reason. Caffeine also has many other known benefits, possible beneficial effects on all-cause mortality, etc, and I'm not sure if we have any research showing the same benefits coming from paraxanthine. Seems like potentially a bit of a waste just to be able to get the stimulant effect a couple of hours closer to sleep time.

by drakonka

4/10/2026 at 2:31:43 PM

This is a distinct claim. Caffeine can disrupt sleep even 48 hours later, a little bit; It is traditionally modelled with an elimination half-life of 5 hours, meaning 1/2 effect at 5 hours, 1/4 effect at 10 hours, 1/8 effect at 15 hours, an exponential decay curve.

The claim being made is that due to cascading decay of a secondary metabolite that does a lot of the work producing the clinical effect, caffeine elimination is a much more linear, slow process that only reaches half effect at around 10 hours and 1/4 effect at 17 hours, 1/8 effect at 23 hours.

by mapt

4/10/2026 at 2:40:58 PM

This may explain why cold turkey effects for me take 24h to start

by mememememememo

4/10/2026 at 3:09:32 PM

I went decaf drinks only back in 2024. I was fine and thinking “what’s the big deal” until day three. I will never forget that day. So horrible.

Still decaf only. Has been a pretty positive change for me. Kicked the soda habit completely. Sleep is better. I find I’m even all day. I generally only get tired when I’m bored.

by ectospheno

4/10/2026 at 11:27:31 PM

Decaf only is great for coffee lovers. Instant decaf is of course just a way to spoil perfectly good hot water. But decaf beans from a good roaster are good then grind and make what you desire - espresso, pour over, french press, moka etc.

Maybe preground OK for non-espresso too?

by mememememememo

4/10/2026 at 3:30:49 PM

Just because the halflife leaves a measurable amount in your system, doesn't mean that that amount is enough for measurable outcomes.

In your example, a 200 mg caffeine intake in the morning, least to 100mg at noon, 50mg at 5PM, 25mg at 10PM. Yes that means you still have 25mg of caffeine. But it's unlikely to have an outcome you can measure since it's below a minimum threshold.

by malfist

4/10/2026 at 4:38:40 PM

This depends on your genetics - there are different groups of caffeine metabolizers. I'm in the group that's super sensitive to caffeine and I can feel effects from less than 20mg.

by Mezzie

4/10/2026 at 7:37:59 PM

Sure, but you're consumption is probably lower.

by malfist

4/10/2026 at 7:42:43 PM

"Caffeine can disrupt sleep even 48 hours later, a little bit;"

The literature for AASM protocols suggests 41 hours without caffeine is enough to safely control for those potential effects

by 1vuio0pswjnm7

4/10/2026 at 2:09:36 PM

This article makes the case for paraxanthine supplements; 80% of caffeine is metabolized into paraxanthine anyway, and it turns out paraxanthine behaves a bit more like we (apparently wrongly) assume caffeine works.

But the real question is: does it taste as good as espresso?

by bensyverson

4/10/2026 at 2:27:23 PM

> does it taste as good as espresso?

Coffee is an acquired taste, I think. People conditions themselves to like the bitter taste of coffee over time. I remember hating the taste of coffee (or beer, for example) in childhood.

by nlitened

4/10/2026 at 2:37:06 PM

Weirdly enough, I loved coffee from the first time I tried it, at maybe 13. Even though, looking back, it must have been terrible coffee, it was at something vaguely model UN like thing our entire class went to in an overnight trip. Obviously not enough sleep was had. A vending machine (in the late 90s) provided coffee...

by anarazel

4/10/2026 at 3:10:08 PM

Yes, I also tried coffee first time when in England when 13, and it was like a revelation. I understand that beer and cigarettes are an acquired taste, they tasted terrible, but coffee was a love at first sip.

by _glass

4/10/2026 at 2:45:27 PM

> it must have been terrible coffee

Douglas Adams nailed the quality of tea from a vending machine, "almost, but not quite, entirely unlike tea", and that era of coffee machines weren't much better at coffee.

by xnorswap

4/10/2026 at 2:31:13 PM

I’ve heard that bitterness affects children more intensely. So I wonder how much of it is an acquired taste vs bitterness just becoming “milder” over time.

by Xcelerate

4/10/2026 at 2:54:38 PM

My three year old loves the taste of matcha. Even when I don't prepare it quite right and it turns out very bitter. He's pretty picky about near everything else. I think it's acquisition through mimicry.

by yonaguska

4/10/2026 at 3:03:25 PM

Matcha is one of the more concentrated amino acids drinks you can make; given how hungry I remember being as a kid, I bet it tastes like liquid gold. And if you’re in a climate that tolerates rhododendrons you can plant a camellia sinensis bush for it straight from the vine as a bridge from matcha to steeped tea, steaming and roasting, etc.

by altairprime

4/10/2026 at 4:24:53 PM

> Matcha is one of the more concentrated amino acids drinks

Matcha is virtually entirely water. Multiple sources say that matcha has about 270 mg of amino acids per serving. Even if matcha powder were 100% amino acids (which would taste vile), a 2g serving would still be 2g.

Milk has about 4.5 grams of amino acid content per 100g (less than half a cup).

by dpark

4/10/2026 at 4:35:36 PM

Yes, that’s one of the reasons dairy matcha lattes taste so good: not only is it more densely amino, but it’s also more broadly amino (e.g. milk is not particularly high in L-theanine), and the sweetness of the milk offsets the bitterness of the matcha, which lets you ramp up the density further beyond 2g if you like.

by altairprime

4/10/2026 at 4:55:45 PM

What I mean to say is that matcha is almost devoid of amino acid content. It’s basically a small cup of water. The small amounts of various compounds may have some beneficial effects, but amino acids are abundant in many foods and drinks. You don’t need to get them in micro doses from matcha.

Matcha may be tasty. It’s not a good source of aminos.

by dpark

4/10/2026 at 5:44:30 PM

Okay.

by altairprime

4/10/2026 at 2:30:45 PM

It's definitely an acquired taste. But an espresso doesn't have to be overwhelmingly bitter! It can be almost sweet if it's extracted well.

by bensyverson

4/10/2026 at 2:45:23 PM

Regular coffee, too, can be very delicate, minimally bitter, giving herbal or strong tea-like notes, among other things.

I've not gotten that kind of profile out of anything but fairly-expensive beans roasted within the last couple of weeks, though. I've never seen it out of even mid-priced beans, nor anything nationally distributed. It's practically a totally different drink from what you get if you ask for a coffee in most contexts.

Iced coffee and cold brew are also fairly different. I find middling beans can make a much milder and more pleasant cold brew coffee than hot. Tiny (like, a teaspoon) splash of cream or milk and it takes the bitter edge all but completely off, to my taste anyway.

by lamasery

4/10/2026 at 3:15:08 PM

> I've not gotten that kind of profile out of anything but fairly-expensive beans roasted within the last couple of weeks, though.

Good beans will last more than 2 weeks, but yes—just as you wouldn't judge all sushi based on gas station sushi, we shouldn't judge coffee based on months-old pre-ground grocery store roasts.

by bensyverson

4/10/2026 at 6:34:04 PM

> we shouldn't judge coffee based on months-old pre-ground grocery store roasts.

Next you'll be claiming that we shouldn't judge sushi based on months-old grocery store sushi.

by DougMerritt

4/10/2026 at 4:58:20 PM

>Coffee is an acquired taste, I think

Billions all over the world managed to acquire it just fine.

If that's an acquired taste, I doubt 99% of drinks that aren't an acquired taste would do much better, assuming there's anything doing better than coffee to begin with.

Not even Cola and tea come close.

by coldtea

4/10/2026 at 2:55:30 PM

I now like bitters and soda, and I didn’t like bitter as a kid, so I think there might also be shifts in favor of bitter unrelated to coffee. Perhaps the same thing that leads people to appreciate spicy or sour as experiences broaden.

by altairprime

4/10/2026 at 6:36:51 PM

Years ago, somewhere I read that children have a genetically-based urge to avoid bitter flavors, since they may signal natural poisons, whereas adults can judge better, so the urge is lessened.

(And even if that source were true, that wouldn't make the genetic effect an absolute; it would depend on individual genetics and the variable expression of those genes. And probably on the individual's experience, either as a child or as an adult.)

by DougMerritt

4/10/2026 at 3:24:25 PM

but why? i have to add so much milk and sugar to mask the bitterness that, combined with the negative effects, i asked myself, why do i even bother? i might as well just drink hot milk with sugar instead. now i only drink coffee if i need the energy and waking effects and nothing else sugary is available, which happens once a year, at most.

by em-bee

4/10/2026 at 3:32:22 PM

This is not universal. I only drink espresso without sugar or milk, because I love the taste of a strong coffee.

by integralid

4/10/2026 at 2:36:27 PM

That is entirely dependent on your diet as a child. I know children that love bitter or sour/fermented foods. Not to mention they dislike things that are overly sweet.

I wouldn't be surprised if all tastes are essentially "acquired".

by nightski

4/10/2026 at 8:18:49 PM

Speak for yourself. The bitter taste is what I like. When I don't like a cup of coffee, it's always going to be for being too sour. (Which can be masked pretty well with milk or a substitute, mind.)

I agree with your main point, though. I hated coffee most of my life. Even the smell made me feel ill. At some point, I flipped. I've always liked tea, fwiw.

I guess I don't hate beer as much as I used to. Still don't like it, though. Maybe another few decades?

by sfink

4/10/2026 at 3:26:04 PM

> But the real question is: does it taste as good as espresso?

I don’t know where you live, but in Italy it’s extremely difficult to find a good espresso; you must go in "specialty coffee" places to taste real coffee, as all the bars use cheap coffee that tastes burnt. Ironically, it’s a country that takes pride in its coffee "tradition" but doesn’t know what coffee tastes like. The experience is the same in France, without the "tradition" thing.

by hk__2

4/10/2026 at 2:20:46 PM

I'd imagine it would not be hard to breed/engineer a coffee plant that produces more paraxanthine than caffeine. The plants take 5 years to mature so getting a crop to market would take a while though.

by ortusdux

4/10/2026 at 3:22:15 PM

I accustomed myself to drinking coffee black. Then decaf. And later I tried camomile tea.

I found the need I really needed satisfied was a warm cup of something to curl my hands around in the morning, and they all worked after I let them. ymmv.

by m463

4/10/2026 at 3:07:18 PM

I can understand espresso being drunk for many reasons, but none of them are "tasting good".

by Sharlin

4/10/2026 at 3:09:43 PM

I actually envy you, because having my first truly good espresso was an experience I wish I could relive

by bensyverson

4/10/2026 at 3:11:18 PM

Cafes that care about their coffee can have very good tasting espresso, but cafes that don't care will produce burnt bitter water. There's also Cafecito, which is basically liquid crack.

by 0xbadcafebee

4/10/2026 at 5:26:43 PM

> There's also Cafecito, which is basically liquid crack.

Is that a warning or an endorsement?

by jjk166

4/10/2026 at 6:46:41 PM

Both!

by 0xbadcafebee

4/10/2026 at 3:18:18 PM

I'm surprised the author didn't mention the other argument for paraxanthine being less addictive than caffeine: it has a less acute/peaky curve of adenosine blocking.

I'm not a biologist, but I'm under the impression that your body uses the heuristic of "the more acutely a neurotransmitter is suddenly flooded into our system, the more of a homeostatic counter-response we're going to launch in the form of things like dopamine downregulation (etc, depending upon what neurutransmitter we're talking about)".

I'm not entirely sure this is true, but it seems to be corroborated by other researchers (e.g. Anna Lembke in her book Dopamine Nation, which isn't about caffeine though).

This is why substances like theacrine claim to offer even less tolerance than paraxanthine: it has a super gradual adenosine-blocking curve, with super long half-life (like 12-16 hours, IIRC). So when you take one theacrine, you won't notice it for hours, but its effects will last longer than one day (though I forget what its interaction with sleep is supposed to be?).

by georgewsinger

4/11/2026 at 7:57:36 AM

Very interesting! An aside and fishing lazily: I am one of those people where caffeine has a very strong and long lasting effect. I don't have caffeine after about 9am or it affects my sleep that night. I love drinking coffee, and fortunately for me it seems like decaf got way better and widely available recently. Did something happen there?

by thenoblesunfish

4/10/2026 at 2:56:16 PM

There are some fairly common genes that can drastically effect the strength and duration of caffeine so your experience may vary. For me the effect is very strong and one cup lasts all day, even as a habitual consumer.

by cjbgkagh

4/10/2026 at 3:09:47 PM

Great point. I'm a fast metabolizer, it's highly individualized.

by oasisbob

4/11/2026 at 7:55:50 AM

Caffeine++* actually uses the 5 hours as default, looks like I can make the formula more correct based on this article. *My app.

by borisyurkevich

4/10/2026 at 2:15:10 PM

Its like a 45 minute decay - Im not shaking the cup's shaking. I can quit anytime I want, I just dont want to.

by blitzar

4/10/2026 at 2:17:45 PM

[flagged]

by supliminal

4/10/2026 at 3:31:52 PM

Pharmacokinetics (in this case: half-life in the central(venous) compartment, totally neglecting the distribution to the site of primary activity, the CNS) is only half of the truth.

You have to consider pharmacodynamics: where is the site of action located, where are the receptors located. And how well do caffein and paraxanthine distribute to this compartment.

Soiler: Most metabolites are more hydrophilic than respective parent compounds (biological sense of metabolism: to increase renal clearance of xenobiotics). Therefore, receptor affinity alone tells you little about the relative contribution of any metabolite for the pharmacological effect observed.

And to complicate things even more: Long-half life metabolites are only ONE potential reason for prolonged biological effects.

by bembem_c

4/10/2026 at 3:29:58 PM

Fun fact smoking reduces caffeine half-life up to 50% by upregulating the enzymes which break it down, which affect paraxanthine as well.

by sharpshadow

4/10/2026 at 4:16:47 PM

Smoking in general? Tobacco specifically?

by R_D_Olivaw

4/10/2026 at 1:49:53 PM

> Importantly, the primary metabolites also block adenosine receptors.

Biochemistry is rarely a one-and-done event it would seem.

by uticus

4/10/2026 at 2:32:55 PM

For me a coffee is more kind of a ritual addiction.

by NoiseBert69

4/10/2026 at 2:48:53 PM

Making coffee is often the only part of my day that I have control over.

by Xerox9213

4/10/2026 at 3:24:13 PM

I switched to cocoa. Replaces the ritual at least. I still miss the boost though.

by bilsbie

4/10/2026 at 3:00:42 PM

That's an interesting takes. I found it quite suspicious at first, especially because it doesn't present well the myths that it's trying to debunk: are we talking abouy caffeine half life or its effects; and is that 5h half life related to the metabolism of caffeine, or related to its effects.

It looks like pharmacokinetics (ie how long caffeine stays in blood) is what's been studied mostly, and that's where the 5h timeline is coming from. I couldn't find papers on the timeline of pharmacodynamics of caffeine (how long it has effects).

That's an interesting gap this article is underlining!

by charles_f

4/10/2026 at 1:58:14 PM

I haven’t come across lesswrong before! Great site and this caffeine article is great presentation of data.

by meitham

4/10/2026 at 2:11:06 PM

I feel it my due diligence to advise you that LessWrong is closely associated with the rationalists and all that comes with them. It is worth doing a tad of research into the rationalist community and Eliezer Yudkowsky before going too deep down the LessWrong rabbit hole. https://en.wikipedia.org/wiki/Rationalist_community

by OuterVale

4/10/2026 at 2:25:44 PM

Regardless of the community,

Harry Potter and the Methods of Rationality is worth a read.

https://hpmor.com/chapter/1

Or a listen: https://hpmorpodcast.com/?page_id=56

by yehoshuapw

4/10/2026 at 3:21:59 PM

I found it pretty boring, to be honest. Felt like an excuse for the author to show off how smart they thought they were, without really any skill at characterization or meaningful plot.

And like, I'm not a writing snob. I read fanfic by amateur authors. But HPMOR just doesn't do much of anything interesting.

by fwip

4/10/2026 at 5:32:14 PM

There's lots of valid critiques of HPMOR (I recently reread it and the early chapters are painfully obnoxious), but I think "no meaningful plot" and "doesn't do anything interesting" are objectively false. It has like a dozen interacting plotlines, and is massively different from any other HP fanfic and most media in general. It is popular for a reason. If you dropped it early, I'd encourage you to try again.

by stratos123

4/10/2026 at 11:18:50 PM

If I remember right, I dropped it after about 40 chapters.

I think interesting is more a subjective thing than objective, also.

by fwip

4/10/2026 at 2:28:23 PM

One can take many good ideas from less wrong, yudkowsky et al without adopting a rationalist identity. Sure, it attracted wackos and they made a cult or two. But that could happen to anyone!

by embwbam

4/10/2026 at 3:22:54 PM

> without adopting a rationalist identity

Aha: "identity". You nailed the misgivings I couldn't articulate. Thank you.

by specialist

4/10/2026 at 2:14:56 PM

>the rationalists and all that comes with them.

What does that mean?

by Zababa

4/10/2026 at 2:25:35 PM

Probably referring to https://en.wikipedia.org/wiki/TESCREAL

or, if you don't buy into the "they're all the same" arguments, at least beware of the arguments against utilitarianism https://en.wikipedia.org/wiki/Utilitarianism

by kreyenborgi

4/11/2026 at 8:07:13 AM

I couldn’t be farther from the rationalists in my views but there are definitely a lot of valjd arguments against utilitariansim…

by xoac

4/11/2026 at 8:29:31 AM

I would change your "but" to "and"? But maybe my comment wasn't very clear. The dangers of phone typing.

I meant that one should acquaint oneself with the criticisms of utilitarianism, if one wants to understand what it is people react to in rationalism and related communities.

by kreyenborgi

4/10/2026 at 2:41:57 PM

Yeah but like:

>Writing in Asterisk, a magazine related to effective altruism, Ozy Brennan criticized Gebru's and Torres's grouping of different philosophies as if they were a "monolithic" movement. Brennan argues Torres has misunderstood these different philosophies, and has taken philosophical thought experiments out of context.[21] Similarly, Oliver Habryka of LessWrong has criticized the concept, saying: "I've never in my life met a cosmist; apparently I'm great friends with them. Apparently, I'm like in cahoots [with them]."

The people that coined TESCREAL seem to not really be related to rationalists, and seem to have coined a term for "those vaguely related ideas from people that do some stuff we consider wrong and we consider bad". "Evil people from San Francisco" could work just as well I think.

And wait, shouldn't I beware arguments for utilitarianism rather than against? If that's what you meant yeah I agree, especially pushed to the extreme it leads you in very weird places.

by Zababa

4/11/2026 at 8:33:05 AM

I meant to write "be aware of arguments against". I think the asker will find enough arguments for utilitarianism in those blogs ;)

by kreyenborgi

4/10/2026 at 3:05:26 PM

I know nothing about the drama, but treating "utilitarianism" as if it is one thing or that a particular person or group's position is identical to utilitarianism seems ironic in the context. It is like claiming all pizza is bad because I went to dominoes and didn't like the experience.

by tasty_freeze

4/10/2026 at 2:57:15 PM

I'm not sure what the parent meant by "beware arguments against utilitarianism" - there is nothing wrong with arguing for or against utilitarianism. It's a popular moral philosophy.

You should beware of bad utilitarian arguments though, which is where you often get the real "gotta break a few eggs to make an omelette" kind of arguments that justify all manners of atrocity in service of some narrow hypothetical future good.

Like when Marc Andreessen says we should consider anyone who would do something to slow down or regulate AI advancement murderers of future humans. Bad utilitarianism right there.

Proper utilitarians are concerned with the net difference between all positive and negative consequences of actions.

by SmirkingRevenge

4/10/2026 at 3:41:47 PM

People often think they have mic-dropped utilitarianism by saying things like, "Oh, so if two people get a lot of joy by beating up a third person, that is ethical because it is overall net positive?"

A few things wrong with that. First is there is no net happiness formula which utilitarians are proposing. Peter Singer has said more than once that he weights suffering far, far higher than happiness.

Second is that every ethical system has screw cases which make the system look messed up. "Do unto others..." it terrible if you are talking about masochists.

by tasty_freeze

4/10/2026 at 2:22:08 PM

Quick Wikipedia search: https://en.wikipedia.org/wiki/Zizians

Like any group of humans, there are power structures and edge cases that can lead to horrific outcomes. Giving the person that posted the warning the benefit of the doubt, I think what they are saying is that "Rationalist does not necessarily mean positive for humanity, nor even no harm for humanity". This holds for all religions and religion-like movements, of which Rationalism, in this sense, is one.

by WBrentWilliams

4/10/2026 at 2:37:27 PM

I think this holds for basically all movements in which case, I don't really understand the need to flag that website over any website.

Edit: though I don't want to diminish that this specific group is a cult with classical cult techniques like sleep deprivation and with the disastrous consequences often associated with cults.

> They claim to practice unihemispheric sleep (UHS), a form of sleep deprivation intended to "jailbreak" the mind, which they believe can enhance their commitment to their cause.[

by Zababa

4/10/2026 at 2:47:24 PM

> I think this holds for basically all movements in which case, I don't really understand the need to flag that website over any website.

Because it uses the language and thinking patterns of the Rationalists, it serves as a strong indoctrination tool. The site itself isn't bad but, as someone who flirted with those communities as a result of the site, I think the warning is deserved.

by eightysixfour

4/10/2026 at 4:08:07 PM

If you feel like the warning is deserved, and have personal experience, yeah then fair enough. I personally live in the "periphery" (read: not in Berkley or SF or New York) so I think I may see way less of the good and the bad.

by Zababa

4/10/2026 at 3:10:34 PM

It's a particular variety of "everyone else is wrong (and maybe a bit stupid)".

Like, sure, sometimes you get popular nonsense like recovered memories or accidental fires can't be as hot as intentional fires or shaken-baby syndrome or bite-mark analysis. But a lot of times, everyone isn't wrong and you've just overlooked something critical or misdefined the problem.

by tbrownaw

4/10/2026 at 6:10:52 PM

> Like, sure, sometimes you get popular nonsense like recovered memories or accidental fires can't be as hot as intentional fires or shaken-baby syndrome or bite-mark analysis. But a lot of times, everyone isn't wrong and you've just overlooked something critical or misdefined the problem.

The older I get, the more I find that everyone is wrong. It's fucking astounding how much stuff either was never actually checked, or is true only under very select circumstances with those caveats being widely ignored. For example at work right now we have been using a test for 40 years that was developed around the idea that our product absorbed air - chemical variation would lead to extreme differences in results and you can't retest an item for at least 24 hours because it will still be affected. Turns out that none of that was true, all the error we were getting was from temperature change, the items can be retested after 45 seconds. 40 years and no one took 30 minutes to verify this claim which costs us millions of dollars per year. And this is just the example from this past week. I've probably seen several hundred such cases of completely unjustified claims being treated as gospel truth.

I can't speak for the countless things I've never tested, but if nearly everything I do test is wrong, across numerous fields full of very intelligent people, it doesn't give me much confidence about everything else. We live in a world that values simplicity and confidence, not nuance and rigorous verification. I've gotten to the point where I don't trust anything without verification, not even my own past work.

by jjk166

4/10/2026 at 5:47:53 PM

> It's a particular variety of "everyone else is wrong (and maybe a bit stupid)".

Gestures at the current state of the world

Not that adopting rationalist modes of thinking will fix the problem, of course. Teach rationalist principles to an idiot and you will have a slightly more rational idiot, who will reason himself into absurdity. Teach them to a manipulative, amoral psychopath and you will have a more skillful manipulator.

Rationalist principles and methods provide superior tools for thinking through some complex problems, but they say nothing about foundational ethics (other than pointing out possible sources for the many different systems of ethical beliefs). And they cannot be wielded effectively by people who lack the ability to decouple, to think abstractly, or to create extended “chains” of thoughts and keep them in working memory.

One should be suspicious of anyone who claims that rationalism is a panacea, or alternatively that it is somehow a problem per se. It’s a neutral set of tools, a community who wants to improve those tools, and a small group hanging off the edge who have unrealistic and/or harmful views of how those tools should be applied. Unfortunately this third minority is presented by anti-rationalists as the core of rationalism. In reality, they are easily avoided unless you hold the same core values.

(I say this as a long time observer who appreciates their work but does not consider myself a part of the “rationalist” community.)

by iamnothere

4/10/2026 at 5:45:56 PM

https://en.wikipedia.org/wiki/Roko%27s_basilisk

Imagine dressing Pascal's Wager up in blinking lights and considering yourself a rationalist.

Yudkowsky banned discussion of it for 5 years because he considered it a threat

by mrguyorama

4/10/2026 at 3:04:14 PM

Nicotine is also a nice alternative to coffee. I still drink coffee but past late morning I'll usually reach for nicotine because the effect is much shorter.

It also has neuro-protective effects if you're an older gentleman.

by siliconc0w

4/10/2026 at 3:10:07 PM

It's also cripplingly addictive. Ask me how I know.

by vrganj

4/11/2026 at 8:46:49 AM

I have smoked for 14 years and hated every second of it until I quit. Nicotine is not cripplingly addictive. Inhaling tobacco (or electronic cigarette) vapour by lung is crippingly addictive.

Years later, I replaced my ADHD medication with low-strength nicotine patches and I find it as effective, cheaper, longer-lasting and with less addictive potential than dexamphetamine. The side effects when I forget a patch are much less than not having my morning cup of coffee — just extremely distractable and lower energy.

Smoking is terrible, but I wish people learned that the effects of smoking are much more intense from the effects of pure nicotine.

by sph

4/10/2026 at 3:38:08 PM

> It's also cripplingly addictive.

That very much depends on the medium. It's virtually impossible for a nicotine naive individual to get addicted to losenges or gum.

by unmole

4/11/2026 at 8:49:15 AM

In order of addictive potential, smoking >>>>> lozenges/gum >> nicotine patch.

It's all a matter of how long it takes to reach peak concentration in your blood stream. Smoking takes seconds, lozenges take minutes, a patch takes 2 to 3 hours.

by sph

4/10/2026 at 4:25:28 PM

FYI you can't patent a supplement. You can, however, be the only manufacturer because nobody else noticed it.

by mannyv

4/10/2026 at 2:10:49 PM

This feels like a Gwern blog, or something he'd be interested in.

by michaelcampbell

4/10/2026 at 9:04:30 PM

I used to drink two double-espressos (technically a latte with a double-espresso in it) a day -- one in the morning, one early afternoon -- for many years.

~5 years ago I stopped drinking the afternoon coffee, and have subjectively noticed improvements in my sleep -- less wakeful in the night. It also fits better with my sleep habits, where when I was younger I commonly worked past midnight whereas now I'm asleep by 10 pm and wake up early.

I still drink the morning coffee and I wouldn't switch to another stimulant because the main reason I drink coffee is because I enjoy drinking coffee :)

by insane_dreamer

4/10/2026 at 3:13:08 PM

I generally avoid caffeine at all costs. I'm susceptible to SVT, and I want the Adenosine to work if I should need it. Caffeine blocks Adenosine receptors. But on the rare occasion I have a single can of caffeinated Diet Coke, I experience a crash 48 hours later so profound that I cannot get out of bed that day.

by atlgator

4/10/2026 at 3:10:42 PM

Why change what works? Especially if you enjoy it.

by annoyingnoob

4/10/2026 at 2:55:52 PM

sight correction....caffeine impacts two neuron groups not just one!

Dopamine and Noradrenaline

For dopamine its the competitive for the adenosine part of the dopamine heretodimer....meaning it prevents adenosine from binding and closing the dopamine receptor....

I use the effect on both dopamine and noradrenaline to assist in controlling my ADHD via more herb based means....

But author is yes correct that the metabolism of caffeine in how it breaks down does make the half life of its effects longer than 5 hours...I combine my dose with green tea ECGC which gives me a good focus boost of 12-16 hours...

by fredgrott