Childhood (not so) crackpot theories

[ahippo]

Oh boy this stuff's my bread and butter! Well when I was younger, not sure quite when, but a while ago, I was fiddling with something, probably a remote. I would put it up to my mouth and my siblings would tell me not to. I was just thinking, now why would I want to fiddle with things or put them to my mouth. Well maybe contact with things releases endorphins, or at least some sort of good feeling. That would explain why I want to fiddle with things. Maybe it gets stronger when the areas of the body are more sensitive. Like the lips, of course! The same principal applies to contact with other living things just it's probably stronger with living things. That's why we like to pet our cats or dogs. That's why we hug people. That's why kissing feels good. I don't know about you guys but it makes perfect sense to me. But I'm probably not the first person to think of this.

[Charlie!]

I used to think that the reason clouds move across the sky was because the atmosphere was stationary and the earth was rotating so the clouds would whiz by.

Iirc, this was one of the main Greek arguments against a rotating Earth--if it was rotating, the air would produce massive winds and the buildings would fall down.

A fun thing is that the earth's rotation DOES produce massive winds They're just not all next to the surface.

[Dimetrodon]

So, I had this idea for an infinite energy source. You build a one-way glass mirror in a sphere shape, with the mirror part on the inside, and shine a flashlight into it. The light keeps reflecting off the mirrors in the inside, while you can see it from the outside. Boom! Infinite light source!
Or not.

[kiklion]

When I was in first grade, I remember being diagnosed as color blind. This led me to thinking that perhaps people don't see things the same way, specifically color. For instance every thing you see that is blue, appears to me as yellow. Now we both call it blue because we have been told that an object that looks like that IS blue, however what you see as yellow I see as blue.

I was also very detached from myself constantly viewing my body as nothing more then a tool for me to work with.

[frog42]

My theory from early high school (and still) is that you can't die. Infinite Personal Reality.

When it's about time for you to die from sickness, old age, etc., in your reality, a miracle cure will be found and you'll be saved. Unfortunately, other people can die (in your reality) but will continue on in their own IPR.

[QwertyKey]

I just remembered this today, I had this idea of powering cities using lightning electricity using gigantic batteries(With no knowledge of electricity at the time).

Looking back, it sounds not just dumb but ridiculous

[lulzfish]

My theory from early high school (and still) is that you can't die. Infinite Personal Reality.

When it's about time for you to die from sickness, old age, etc., in your reality, a miracle cure will be found and you'll be saved. Unfortunately, other people can die (in your reality) but will continue on in their own IPR.

That's called Quantum Immortality.
There's an infinite number of universes, and you can only observe the ones where you continue to live, so you appear to live forever.

It depends on a lot of quantum mechanics that I don't really understand, though, so I can't believe in it.

[Outchanter]

My theory from early high school (and still) is that you can't die. Infinite Personal Reality.

When it's about time for you to die from sickness, old age, etc., in your reality, a miracle cure will be found and you'll be saved. Unfortunately, other people can die (in your reality) but will continue on in their own IPR.

That's called Quantum Immortality.
There's an infinite number of universes, and you can only observe the ones where you continue to live, so you appear to live forever.

It depends on a lot of quantum mechanics that I don't really understand, though, so I can't believe in it.

It also has some rather nasty consequences. For example, if you're caught in a car crash, there will be some universes where you survive, but in most of them you'll be horribly maimed for life. Which, given the immortality part, is a long, long time.

[frog42]

My theory from early high school (and still) is that you can't die. Infinite Personal Reality.

When it's about time for you to die from sickness, old age, etc., in your reality, a miracle cure will be found and you'll be saved. Unfortunately, other people can die (in your reality) but will continue on in their own IPR.

That's called Quantum Immortality.
There's an infinite number of universes, and you can only observe the ones where you continue to live, so you appear to live forever.

It depends on a lot of quantum mechanics that I don't really understand, though, so I can't believe in it.

It also has some rather nasty consequences. For example, if you're caught in a car crash, there will be some universes where you survive, but in most of them you'll be horribly maimed for life. Which, given the immortality part, is a long, long time.

And here I thought I was original. Those consequences sound pretty bad, but what happens when you decide to end your life because of your painful disability and seeming immortality? Either you mess up to the point that you can't even try anymore or they find a way to cure you before you get that far.

As I've grown older, I've aligned my thoughts more with Buddhism though. Maybe you're only quantumly immortal until you're ready to move on.

[userxp]

That's called Quantum Immortality.
There's an infinite number of universes, and you can only observe the ones where you continue to live, so you appear to live forever.

It depends on a lot of quantum mechanics that I don't really understand, though, so I can't believe in it.

I have to say that quantum Immortality sounds good, but makes no sense.
If every possible universe exists, then there is an universe where I have just turned into a chair, a frog, or anything or anyone.

you can only observe the ones where you continue to live

What if my body turns into an exact copy of my father's body? Is it me or is it my father? What if my body disappears from here and appears in china?

Also, quantum immortality should work in the past. I've been dead ever since the big bang, and only less than 20 years ago I started to exist.

[frog42]

I have to say that quantum Immortality sounds good, but makes no sense.
If every possible universe exists, then there is an universe where I have just turned into a chair, a frog, or anything or anyone.
What if my body turns into an exact copy of my father's body? Is it me or is it my father? What if my body disappears from here and appears in china?

Also, quantum immortality should work in the past. I've been dead ever since the big bang, and only less than 20 years ago I started to exist.

I hate it when people assume "infinite universes" implies "absurd universes". There are "infinite universes" because very slight changes can build up over time to create larger ones. I assume in quantum immortality that when you "die", you simply begin to perceive a universe where that diverged JUST ENOUGH to keep you alive.

[phlip]

Spoilered for long and offtopic rambling about quantum immortality.

Spoiler:

Right. If the many-universes model is accurate, then there may well be a universe somewhere where you suddenly disappear. Quantum tunnelling and such. It doesn't make it any more likely that this would happen than in any other QM model. Say there's a one-in-a-googol chance that a particular crazy thing will happen, just from quantum nonsense. In a single-universe model, that just means exactly what it says... it has a one-in-a-googol chance of happening. In a many-universe model, there exist universes where the crazy thing happens... but for every universe where it happens, there are a googol more where it doesn't... so the chance that you're observing one where it happens is, you guessed it, one-in-a-googol. Where the interesting things start to come in is when your ability to observe the result is not independent of the result itself.

The standard thought experiment is a flawless quantum computer connected to a doomsday device that can instantly destroy the entire universe - just, at a certain point in time, the universe ceases to exist. Trying to talk about what happens after that time is as meaningless as asking what happened before the big bang, or what's north of the north pole. Now, this computer uses quantum randomness to generate a single bit, 0 or 1. It then writes the value on a piece of paper. If it's a 0 it then stops, if it's a 1 it activates the doomsday device as it writes the number. You activate it, and then look at the number it wrote down... it will be a 0... because if it was a 1, you wouldn't have had the opportunity to look at the number.

Now, in a single-universe model this just means that there's a 50% chance that the universe will survive and we'll see a 0... and a 50% chance that the universe will be destroyed and we won't see anything. There won't even be an "us" to do any observing. The weak anthropic principle applies - if we are able to make an observation, we shouldn't be surprised that the observation matches the requirements for observation to be possible.

However, in a many-universes model, the strong anthropic principle applies... after the machine is activated, half as many universes will exist, in all of which the value on the paper is 0. So the standard probability calculation - number of universes where the value on the paper is 0, divided by the number of universes... gives 100%. The computer will always write 0.

All of which is great for a philosophy debate, but isn't science at all... there's nothing testable here. In both cases, where observations are possible, the observations will match.

Quantum immortality is taking that premise, and applying it to a single person. It ties into another philosophical untestable thing: "I know that I am conscious, and I know I can observe things... but everyone else could all be soulless robots for all I can tell." What if I'm the only real observer of the universe, on some fundamental level? Then if I were to stop observing, it would be basically the same as the universe ending. But even without that... in all situations where I'm able to make an observation, I am still alive. So in the many-universes model, so long as there exists a universe where I am alive (that is, so long as me being alive is physically possible), those universes where I'm alive are the only ones in the probability state-space for my consciousness. Of course, other people dying isn't a problem - that doesn't affect my ability to observe the universe.

Of course, one of the big assumptions this rests on, is the many-universes thing... in a single universe, sure, you'll still be alive as long as you can keep observing stuff, but one day you'll stop being able to observe stuff. Another assumption is that consciousness completely disappears immediately at death... a proposition many religions would disagree on... pretty much any religion that includes any sort of afterlife.

But still, it's fun to think about, if you're into that sort of thing.

[ACU-LP]

One reason why I wouldn't want that quantum such to be true is that everyone you ever love or hold dear will die, and you will end up alone.

[userxp]

I hate it when people assume "infinite universes" implies "absurd universes". There are "infinite universes" because very slight changes can build up over time to create larger ones. I assume in quantum immortality that when you "die", you simply begin to perceive a universe where that diverged JUST ENOUGH to keep you alive.

OK, but first, I'm not sure there can be infinite universes, a lot of them yes, but infinite...
Second, I don't know much about quantum things so I could be entirely wrong, but AFAIK quantum theory means that a particle has a certain probability of "being here" and a lower probability of "being there". Couldn't many very slight changes such as an atom moving out of its place produce a big and apparently absurd change?

[Hydralisk]

If so, your sons have a good chance of being colour-blind, I'm sorry to say.

Colour-blindness really isn't bad. What you lose in the ability to tell light pink from light grey etc, you more than gain in a good topic of conversation at nearly all social events. What you're trying to say is "I'm sorry your sons can't be pilots or bomb defusers", both life threatening jobs.

That's something that's always bugged me. When the terrorists are making the bomb, why do they colour code which wire should be cut first? Surely the disposal teams wouldn't stand a chance if you carefully coloured all the wires one colour? Though I suppose the positioning of the wire would give away which wire did what...

One of my childhood theories entailed building a large solar array in space and having the wire transmitted back down to earth via radiowaves or a really really long wire... bear in mind I was about 7 (This is around '96) and had never heard of dyson spheres etc.

[userxp]

One theory I had was that if you take a really long wire, put electricity in one end and quickly connect it to the other one, electricity would keep going forever in circles.

Wait, wouldn't it happen with superconductor wires? Hmmm....

[
One of my childhood theories entailed building a large solar array in space and having the wire transmitted back down to earth via radiowaves or a really really long wire... bear in mind I was about 7 (This is around '96) and had never heard of dyson spheres etc.

http://www.bloomberg.com/apps/news?pid=20601101&sid=aJ529lsdk9HI

[starfire09]

I used to think (And still often humor myself with it) that when we dream, we create a parallel universe with a whole new set of physics (Hence flying, teleportation, and all the other fun stuff in dreams). What we remember when we wake up is "experiencing" the life of the parallel "us." Of course an entire universe's lifetime elapses during our dreams, but when we wake up we only remember a random memorable part of our parallel life. Of course, this theory means that the universe we live in is somebody's dream, and all the parallel universes we worry ourselves with are other peoples' dreams from the universe "above" ours.

Now I just need to figure out what happens when we're startled awake mid-dream...

[Problem212]

I was looking for a reason not to do my math homework. Naturally, i tried to disprove the logic of Math. (this may offend some of our super nerds and mathematics professors.) I thought: "Well, math didn't just pop out of nowhere, it was thought up by a dreamer like myself." Who exactly thought-up the concept of math? What is math derived from? At what point, as we search for the beginning source of math, do we find out that math is a spider web that is detached from the wall of the universe? What properties relate math to any part of the universe?

I was totally ignored, and then given two consecutive detentions: One for interrupting the classroom, and one for not having my math homework.

[DrZiro]

When I was really little, I thought that it would be possible to make a perpetual engine.
Then I learned about the first law of thermodynamics, so I figured, it should still be possible to make a perpetual engine, as long as it is also a perpetual refrigerator.
Then I learned about the second law, so I figured, it should still be possible to make a perpetual engine, as long as it is also not only a refrigerator but also a radio emitter.
(Since the radio waves are a more entropic form of energy than heat, right?)
I don't think the third law of thermodynamics prevents this, but there might be another law that does. If you know of one, do let me know, so I can move on to the next stage.

Conservation of energy. If your machine goes on forever in the same state and it puts out energy as radio waves, that's infinite energy, which is illegal.

Okay, it wouldn't be able to go on forever, only as long as there is heat. It still sounds rather utopian. It doesn't actually run out of energy, but it does run out of (negative) entropy.

[PM 2Ring]

If every possible universe exists, then there is an universe where I have just turned into a chair, a frog, or anything or anyone.

What if my body turns into an exact copy of my father's body? Is it me or is it my father? What if my body disappears from here and appears in china?

Maybe those ones aren't possible universes. In a Many Worlds Theory, not all apparently conceivable universes exist. Universes have to be consistent.

Also, quantum immortality should work in the past. I've been dead ever since the big bang, and only less than 20 years ago I started to exist.

Very good point.

I think you'd enjoy the Swampman thought experiment.

[tms]

I was 8, if that, when I thought a strong "first contact with extra terrestrials" would be the impetus to get rid of nation states. I mean looking at it now, one is similar to zero... Also, I didn't think any severe conflict between the species was necessary.

[SuicideJunkie]

I think you'd enjoy the Swampman thought experiment.

How does that marble example show anything?
Everyone would have the exact same questions and answers about the marbles regardless of the situation.

I suppose that's the argument against it, given that only a broken, semi-omniscient observer (that perfectly tracks atoms but not information) would be confused.
That same observer would probably go instantly insane if it witnessed an entanglement experiment...

[Opus_723]

I was just thinking to myself the other day that I actually think a lot of the 'explanations' of natural phenomenon in flat-earth theory would be fiendishly clever... if they were coming from a ten-year-old.

Expect for the whole 'sunsets are optical illusions' thing. I feel like even a ten-year-old could do better than that.

But the disk Earth with the South Pole broken out into an ice wall, and the winding solar orbit creating the seasons, would get a chuckle of admiration from me if it was a kid making it up in a fit of imagination.

[Eebster the Great]

I have a model of the Earth that is at odds with both the disk and the globe. I think the Earth is a cylinder, with the sun in the middle. The sun's motion is (to the first approximation) a circle, so that you have day when it is on your side of the cylinder and night when it is on the other. At the equinoxes, the sun's path is over a privileged circle on the cylinder called the equator, and the sun actually traces out a helix from one tropic to the other and back over the course of the year. The "poles" are myths, and you can actually go infinitely far north or south (though it will rapidly become uninhabitable). In the center of the cylinder is a smaller, dark cylinder which blocks out the sun at night and which exerts the complicated gravitational forces required for this motion and for the motions of the moon, planets, and stars. Our eyes have naturally evolved to correct for the east-west curvature, so the path the sun takes appears to curve down toward the horizon rather than slightly upward to meet a horizon curving up even faster. The whole shebang is rotating rapidly, producing what we experience as gravity. Hypothetical Soviet ICBM paths "over the north pole" actually referred to direct shots through the center of the cylinder, past the sun, curving slightly to avoid the dark cylinder.

[Carmeister]

Sounds like you're describing the Ringworld, more or less.

[Eebster the Great]

But like an infinitely wide ring. A cylinder even.

[WriteBrainedJR]

I used to believe that there were nine universes, arranged like a tic-tac-toe board. I had no supporting evidence for this whatsoever, but I was 9 years old and 9 was my favorite number. Stupid theory.

I used to believe that I could create a flying newspaper out of paper and cardboard tubes, and that when I succeeded, this invention would be worth a lot of money. I succeeded in creating a time-consuming yet semi-entertaining way to destroy cardboard tubes, but that's about it. This was a slightly less stupid theory, since it was pre-internet, and the core concept about having a faster news cycle proved to be at least somewhat lucrative.

I used to believe that small animals experience time differently than large animals. Basically, they don't live as long, so shorter lengths of time feel longer to them. I don't entirely disbelieve this theory, because it explains why flies and the like have much better reaction times than people.

I used to believe that all animals with hearts live approximately the same number of heartbeats. That's why small animals with fast heartbeats don't live as long. A corollary to this theory was that the real reason fitness increases life expectancy and obesity decreases it was simply the effect on resting heart rate. I actually kind of still believe this one, too.

I used to believe that, because antimatter particles have the opposite properties of matter particles, that they also move backwards in time. I don't know of an specific evidence disproving this theory, but I don't have any evidence for it, so I guess I just consider it an interesting idea now.

I used to believe emphatically that the bulletpoint in the definition of life requiring that "life is made up of cells" is a ridiculous and arbitrary requirement created specifically to exclude viruses, even though viruses are clearly alive. I actually still believe this, perhaps even more emphatically than I used to. See, at the time, I clearly saw intent, but wondered why someone would intend to do that. Having experienced more of humanity, I'm pretty confident that this entire theory is correct in its observations of human nature even if it's ultimately wrong about viruses.

I used to believe that UFOs exist, but despite having seen them twice, I no longer believe they exist. Seeing is not necessarily believing.

I used to believe that Bigfoot exists, but stopped believing it after investigating and debunking a couple of supposed Bigfoot sightings for friends/acquaintances in my teens. I always found signs of bear activity nearby. I was technically not an adult yet when I revised my theory on Bigfoot to "it's bears and idiots," which I still believe.

[WriteBrainedJR]

I used to believe that there were nine universes, arranged like a tic-tac-toe board. I had no supporting evidence for this whatsoever, but I was 9 years old and 9 was my favorite number. Stupid theory.

I used to believe that I could create a flying newspaper out of paper and cardboard tubes, and that when I succeeded, this invention would be worth a lot of money. I succeeded in creating a time-consuming yet semi-entertaining way to destroy cardboard tubes, but that's about it. This was a slightly less stupid theory, since it was pre-internet, and the core concept about having a faster news cycle proved to be at least somewhat lucrative.

I used to believe that small animals experience time differently than large animals. Basically, they don't live as long, so shorter lengths of time feel longer to them. I don't entirely disbelieve this theory, because it explains why flies and the like have much better reaction times than people.

I used to believe that all animals with hearts live approximately the same number of heartbeats. That's why small animals with fast heartbeats don't live as long. A corollary to this theory was that the real reason fitness increases life expectancy and obesity decreases it was simply the effect on resting heart rate. I actually kind of still believe this one, too.

I used to believe that, because antimatter particles have the opposite properties of matter particles, that they also move backwards in time. I don't know of an specific evidence disproving this theory, but I don't have any evidence for it, so I guess I just consider it an interesting idea now.

I used to believe emphatically that the bulletpoint in the definition of life requiring that "life is made up of cells" is a ridiculous and arbitrary requirement created specifically to exclude viruses, even though viruses are clearly alive. I actually still believe this, perhaps even more emphatically than I used to. See, at the time, I clearly saw intent, but wondered why someone would intend to do that. Having experienced more of humanity, I'm pretty confident that this theory is entirely correct in its observations of human nature even if it's ultimately wrong about viruses.

I used to believe that UFOs exist, but despite having seen them twice, I no longer believe they exist. Seeing is not necessarily believing.

I used to believe that Bigfoot exists, but stopped believing it after investigating and debunking a couple of supposed Bigfoot sightings for friends/acquaintances in my teens. I always found signs of bear activity nearby. I was technically not an adult yet when I revised my theory on Bigfoot to "it's bears and idiots," which I still believe.

[Pfhorrest]

Some of those things— the time perception, heartbeat life time, and antimatter ones— are actually known to be true.

[WriteBrainedJR]

Some of those things— the time perception, heartbeat life time, and antimatter ones— are actually known to be true.

I wish someone had told me. My parents told me they were ridiculous.

[Eebster the Great]

I don't know that the "heartbeat lifetime" is true really. There are so many other things that are more important to our lifespan, and it's not like there is some upper bound imposed by "number of heartbeats" either. Exercising is good for us in a variety of ways that don't really boil down to our resting heart rate.

Antimatter is identical to time-reversed matter due to CPT symmetry, so that one is pretty legit. It's not quite so impressive though when you realize that in most interactions, it is also identical to regular matter.

I don't think there is any such evidence that shorter-lived animals as a rule perceive time differently than longer-lived animals.

[Xanthir]

Heartbeat-lifespan isn't *strictly* true, but there is a reasonable inter-species correlation between resting heart rate and average lifespan, so the product of the two is *very roughly* constant across species.

Similarly, size vs time perception is reasonable; at minimum, smaller things have shorter nerve lengths, so the time just to *traverse* the entire nervous system is shorter.

[Eebster the Great]

No I don't think so. The reason animals with high resting heart rates don't live as long is because they are small, not because they run out of heartbeats sooner. There is no maximum number of beats, which was sort of the point of the claim. In fact, a healthy heart would outlive a typical individual of any species.

Also, smaller animals have smaller brains, but that doesn't necessarily mean they think faster any more than humans with microcephaly do. It does mean that the response time will be shorter if you prick their foot (central nervous response at least), but I don't think that's relevant.

[Jplus]

I don't know whether there is evidence for a general correlation between perception of time and body size, but I do find it plausible. Anyway, flies really do think much faster than humans. Also, my impression is that my cats think faster than I do (even if they understand less overall).

[Eebster the Great]

It's hard for me to visualize a fly "thinking." I know that they do, in the sense that they make decisions, learn, remember, etc., but their lack of any true brain makes me suspect their cognitive processes are very different from mine. But I would be willing to believe that for a good definition of "think," flies think faster than humans, in the sense that a single "thought" will last less time in the nervous system and a single fly might even have most of them per second. But their thoughts are so much less complex (I guess), that they might not actually process more information per second in an information-theoretic sense.

On the other hand, it is possible that they do process information more quickly than humans but that without the type of abstraction we are capable of, this simply doesn't amount too much. For instance, their many eyes require a lot of visual processing to make sense of, but at the end of the day, they have only a relative few possible behaviors for that large amount of information. But I find this possibility less likely, since they simply have so few neurons. It seems like if we are counting all sorts of neural activity, surely the animal with the greatest quantity of active neurons should win.

Just speculating.

[Jplus]

Going off-topic, so spoilering my response to Eebster the Great.

Spoiler:

As you say, you're just speculating. Besides the TED talk which is based on serious research, so am I, at least with regard to the specific question of the speed of thought of a fly.

I find it highly ironic, if unfair, that we (meaning nearly all humans) make lots of assumptions about the way animals from other species (don't) think. They are not as pervasively present on the planet as humans, so surely there must be all kinds of thoughts they can't have that we can. Or they have fewer neurons, so surely their thoughts must be simpler. It all seems to make a lot of sense at first sight, but the assumptions are largely unjustified. We simply seem to want other animals to be cognitively inferior to us, especially the ones that are much smaller or that appear to be much simpler than ourselves.

For me, as a human, it is impossible to know what you, a fellow human, think, let alone what is the speed or the complexity of your thoughts. I can choose to trust your verbal report of what you think, but I have no guarantee that it is true. For animals from other species, the situation is even worse, because they cannot give a verbal report that a human can understand in enough detail to draw conclusions about their way of thinking. We have no way at all to directly gauge the speed or the complexity of the thoughts of other animals. The best we can do is to test performance on a particular task that we consider indicative of some mode of thinking.

I studied biology and linguistics during my bachelors. I learned about several nice experiments to measure cognitive performance in animals from other species. Generally, experiments to confirm that certain animals can do certain things are much simpler to set up than experiments that conclusively falsify such a feature. As a result, there is not much evidence in favour of the assumption that smaller animals think simpler and actually a lot against it. I'll list the examples I can think of from the top of my head:

• A bumblebee species (I think, otherwise a bee species) was shown to be able to keep 10 things in working memory at the same time. Humans are commonly cited as having only 7 things in working memory at the same time. Personally, I believe I can keep at most 5.
• In a related study with fake flowers with newly invented features, (bumble)bees were shown to be able to abstract from flower features. (There is a whole field of study on reasoning in pollinators, which is called cognitive ecology. What I read from it was all about bees and bumblebees. I even did a small field experiment on this myself.)
• A grey parrot called Alex was shown to be able to abstract as well, although this case took a lot of training.
• Several corvid and great ape species have been shown to be able to plan ahead multiple steps. I would argue that in some of these experiments, some non-human individuals demonstrated performance that some healthy humans wouldn't be able to match. Imagine a task in which you need a key to open a box that contains a key, etcetera, five levels deep, in order to ultimately get a banana; that kind of stuff.
• In a task in which digits are briefly shown in random positions on a touch screen, after which all digits are covered by rectangles and the tested individual must tap the rectangles in the order of the digits, chimpanzees vastly outperformed humans both in speed and reliability. Basically, Chimpanzees all seem to have perfect photographic memory, although that's probably an anthropomorphic way to explain the result.
• Great apes, dolphins, Indian elephants and cleaner wrasse (a tiny fish) were shown to be able to recognize themselves in a mirror.
• Octopuses are known to quickly figure out how to screw and unscrew a jar.
• Some corvids make feint moves when hiding food in order to mislead other birds. This suggests that they understand what another individual can and cannot know (theory of mind).
• In a task in which an asymmetrical image is shown, as well as a rotated version that may or may not be mirrored, and the tested individual must decide whether the image was mirrored or not, pigeons and a few other species vastly outperformed humans in speed and accuracy.

While none of this proves human-like thought in any particular species, each example does clearly show for one type of task that performance does not need to correlate with brain size, at least not nearly as much as we might be inclined to believe. Also, some of these experiments demonstrate that a smaller brain can be faster than a larger brain while also executing the task in question at least equally well.

So far for science, now my personal speculation again. I don't think that the number of neurons in a brain correlates much with complexity of thought at all. By analogy, the Intel 4004 only had 2300 transistors, while present day CPUs and SOCs have billions of transistors. Yet, both are Turing complete and can compute the exact same things in principle. In the case of animal brains, I think neuron count is a function of body size as well as of the presence of special purpose networks. In the specific case of humans, the brains are known to be larger than you'd expect from the general trend between body size and brain size, but I suspect you can "explain away" the "surplus" by the following special purposes:

• Fine motor skills. Humans balance on two legs, have opposable thumbs and can throw things, other primates swing through treetops and also have opposable thumbs, dolphins are extremely able swimmers, octopuses have eight independently movable joint-free arms with hundreds of independently movable suckers. All of these animals needs lots of neurons just to process all that movement. The majority of our neurons is in the cerebellum, which has exactly this task.
• Intricate social structure. We need to take very elaborate social-emotional structures into account, involving authority, solidarity, guilt, trust, etcetera. We have a relatively large frontal lobe, which is specialized in this type of thing.
• Language: much of our left temporal lobe is involved in producing a signal that gives a highly detailed account of what we're thinking. It appears this account is much more detailed than in any other species.

Of course, you can argue that these are all forms of complexity. However, you'll find that I didn't mention some of the things that I think are more general and more fundamental to complexity of thought: memory, abstraction, planning, etcetera. I don't think you need a lot of neurons for those. The experiments I mentioned above seem to support this.

This leaves the obvious question how humans can be so much more technologically advanced than other species, if our thoughts aren't necessarily more complex. I think this has very little to do with the complexity of thought of individual humans; a single human without education cannot invent or build an airplane any more than a single chimpanzee or a single beetle can do it. Rather, our capacity for language enables us to collectively share and accumulate insights to the point where we are able to build airplanes.

Regarding speed of thought, metabolic rate and signal travel distance were already mentioned as possible enabling factors for smaller animals to think faster. I find it plausible that there is a selection pressure that positively reinforces this. For example, for a prey, it is advantageous to be able to think faster than a predator and vice versa. Given such selection pressure, I think prey and predator species will tend to evolve to think as fast as their body size allows.