Sure, but “likely” is still making a kind of claim. I’m disputing we even have grounds for saying it’s likely.
It’s possible an ET species could have a nervous system similar to ours, sure. I don’t see any reason to say more than that however.
So…they are the exception that proves the rule?
On the face of it, this seems contrary to the point you are trying to make.
Now imagine a planet significantly hotter than Earth. Or that is tidally locked to its star (so there are no seasons, and one side is always in daylight, the other in night).
I see no reason to assume this either impossible or even less likely than a goldilocks planet to give rise to (intelligent) life. Especially bearing in mind such planets likely outnumber “habitable zone” worlds.
And indeed, I don’t think you’ve shown that even on a planet as cold as ours it was a necessary first step to be warm-blooded before sentience could arise.
The fact that cephalopods appear to have some compromises…sure, but they’re living in a cool and oxygen-poor environment. There are indeed significant benefits there to being able to breathe surface air and be warm-blooded.
We would expect an intelligent organism to have some kind of highly networked and adaptable structure for signals processing, communication, and general cognition insofar as that is a precursor to being “intelligent”. Whether it would look anything like the mammalian nervous system (myeliniated axions attached to a nuclear body with a tree of dendrite structures forming neurons which convey signals to via synapse transfer and release of neurotransmitters) is questionable, but some equivalent functionality in some form of likely comparable complexity would be a prerequisite for intelligence as we would understand it.
The point of the discussion about cephalopod ectothermy is that while it doesn’t prevent the development of intelligence per se, it does place some significant limits on the innate ability of the organism to extend its reign across a terrestrial environment where thermal regulation by transfer to the environment is reduced to the rather weak convection to air (or whatever atmospheric medium) versus a more efficient liquid medium. This in tern limits the potential energy rate of chemical reactions (e.g. no fire) and places a significant burden on the creature to evolve very specialized mechanisms of thermal regulation that are peculiar to the environment. This isn’t a hard and fast rule; a civilization of intelligent aquatic creatures could certainly develop, using slower non-combustion electrochemical reactions (analogous to the operation of a battery or fuel cell) for energy storage and conversion, and building structures using deposition metallurgy, carbon or calcium materials, or some other material science we haven’t even conceived of as being practical. They could extend their reach into terrestrial or atmospheric environments by the same means that we go into the ocean or space (using SCUBA or vacuum suits with mechanical thermal protection and regulation). It just poses some greater thresholds to basic expansion into their environment and eventual industrialization that (we assume) would go along with high intelligence.
Life on tidally locked worlds has been widely speculated for the very reason you mention (the presumed commonality of such systems). The most pressing argument against them is the very heat you mention; while it is often assumed that hot conditions are preferred to cold in terms of the development of life, there is a threshold above which we cannot reasonably expect chemical systems to be in a stable net thermodynamic equilibrium because of the variation in energy levels coming into the system. (Net equilibrium means that while the mean temperature of the system may vary across a broad distribution, it remains within specified parameters with a mean level that is relatively stable when averaged over time; in other words, an ergodic process.) Life is, at its essence, a thermodynamic regulation system; that is, it accepts energy, mediates it through some organized structure, and rejects the resultant waste heat. This requires thermal gradients, and the higher the input temperature is the larger the gradient has to be in order to be able to establish a net equilibrium system, but not so extreme that it prevents the formation of relatively stable chemical structures. Hence, we’d actually look for life in areas that are moderate to cool (just warm enough to sustain liquid water or some other polar solvent medium) rather than high temperatures and extremely gradients. Planets in a close enough orbit to be tidally locked are unlikely to provide thermodynamic conditions that are suitable for the development of (chemical-based) life regardless of the particulars of the environment.
However, we can’t make the same argument, or indeed, any argument of much substance about life that is not based on organic-like chemistry; but then, we probably wouldn’t readily recognize such life, either, at least without some serious bending of our standard expectations of what comprises life. Realistically, any alien life we do find will probably challenge one or more of the guidelines that I laid out just because of the potential variability that is vastly beyond our experience to even anticipate.
Tidally locked planets have plenty of thermal gradients, and they have the advantage of staying more or less put. To take advantage of them you only need to be in the right place; it is always the right time.
Really, there may well have been a species with complex abstract intelligence living among the dinosaurs. Having perhaps different needs compared to us, they might never have built cities or cars or whatever. And even if they did, what evidence would we expect to find, after 60 million years? For all we know, they were really good at recombinant DNA, the evidence being those ridiculous behemoths they created, and that is it. We should try to extract some from a mosquito in amber and see if there is a message in there, or evidence of tampering.
OK, right there you lose the evolution argument. We evolved with intelligence because we are so small (quick enough breeding cycles) and because we are so vulnerable. Our ancestors were not at the top of the food chain, so adapting intelligence to survive in the middle of it makes sense. Monstrous creatures are less likely to develop intelligence because they have no need of it.
But therein lies the problems; the first, that the gradients are probably very localized (at the boundary between the starward side and lee side) and therefore don’t allow development outside that region; second, that the gradients will probably be extreme; and third, the seeming improbability of holding any atmosphere or permanent bodies of liquid water being sustained on the surface or even in a subsurface region. (While we can’t dismiss chemical life forming in the absence of a liquid medium, I have yet to see a credible proposal for how a complex biochemistry could operate without it.) Of course, we are regularly surprised by conditions we see on planets and large moons in our own solar system, and until we have the ability to somehow image or explore smaller worlds in other systems we won’t have any empirical basis for estimating the conditions on such worlds, but the general consensus is that they’re about as unlikely as small rocky plutoids or asteroids to be a home for life.
Setting aside garden worlds analogous to Earth (about which we can only guess at the frequency with which they occur, as such planets are too small and have too little influence on the F, G, and K stars thought most likely to harbor them) suitable conditons for life to evolve as we know or anticipate it probably exist on large moons heated by tidal friction similar to Europa, Enceladus or Titan and offer good potential for the evolution of complex organic life, and could exist in the atmospheres of icy gas giants.
I suspect the frequency at which ‘life’ based on some organic chemiostry framework is probably quite common throughout the universe, and would offer good odds that we’ll find some evidence of past or present existance in exploring our own solar system. However, we can say little about the conditions which might be suitable to support the development of complex (multicellular or of analogous complexity) life which could develop high intelligence, and even less about the likelihood of such a development under those conditions. It may be common or vanishingly rare, but in either cases, the chances that it would be in the form of something we would identify as being humanoid, or even casually recognizable at all are likely to be astronomically tiny.
Rules out dolphin/whale intelligence, doesn’t it? If the environment is sufficiently rich, intelligence might evolve, rewarded by survival traits not involving manipulation. Being able to predict predator behavior, understanding weather and currents, etc.
It doesn’t have to involve telepathy. Insects communicate with chemicals. Vinge’s aliens communicated by sound. (He worked out the bandwidth of communication between the left and right hemispheres of the human brain, and demonstrated that this information could be coded sonically.) Another SF author had a “hive mind” involving little birds that communicated sonically, and also somatically: they communicated with each other by how they were placed in 3D relative to one another.
(This is, approximately, how real flocks of birds maintain flock cohesion in flight.)
I have heard it suggested that perhaps a large planet in the habitable zone of a M-class dwarf might have a moon that could support life, but I wonder, can a tidally-locked body itself keep a satellite in a stable long-term orbit?
I should qualify that when talking about a “highly intelligent” alien species I’m specifically referring to those capable of developing technology (advanced tool making), industrialization (sophisticated and uniform manufacturing of some type), and sufficient mobility (innate or augmented) to be able to explore their terrestrial environment and beyond. That comes with the implicit assumption that the utility of intellect is industrialization and exploration, and that dolphins and cephalopods and so forth are just flogging around wasting their time eating fish, podding, and copulating while we’re making ourselves useful building bridges, orbiting satellites, and spreading diverse new forms of pornography across our internets. The dolphins, if queried, might respond that they are busy eating fish, podding, and copulationg while we are wasting our lives building useless bridges, lobbing garbage into space, and generally idling away downloading porn on the internets. So, there are definitely multiple points of view on the matter.
A large, icy giant planet is unlikely to become tidally locked; that can generally occur only with smaller, moon-sized planets. The biggest problem with life on a planet (or moon) around a star of spetral class M is that the luminosity is very low (both for dwarves and the much shorter lived off-sequence red giants), requiring the planet in question to either be very, very close (hence, the assumption that a planet would be tidally locked) or would be driven by some source of power other than the star itself (gravitational contraction, tidal, radioactive decay). Generally, we would expect life as we know it to develop around F, G, or K spectral class stars just because they tend to be relatively stable, have a useful level of luminosity, and are generally rich enough in metals to support complex chemistry.
Grin! Okay; my definition would have included non- and pre-technological sapience, although I honestly don’t know if dolphins qualify even in this case. I think they’re intelligent (in the sense of being possessed of advanced symbol-manipulation skills, of which our language is also an example.) But I don’t know well enough to say dogmatically. Anyway, I want to leave the door open for non- and pre-tech “intelligence,” so my dictionary and yours will not necessarily agree.
Not really true- a significant number of the large, hot, gaseous worlds which have been discovered in the last fifteen years are probably tidally locked as well. However they orbit so close to their parent star that they have a year length equivalent to around an Earth day - since they are tidally locked, this means they rotate in the same period with respect to the fixed stars.
What does this imply for surface conditions on such a world? Well, with an absolute rotation speed similar to the Earth, the planet’s thick atmosphere will rotate quite quickly, spreading heat more evenly over the planet. Here’s an interesting simulation by Cho and James
Atmospheric dynamics of tidally synchronized extrasolar planets http://rsta.royalsocietypublishing.org/content/366/1884/4477
This is a fascinating area of study, all entirely hypothetical at the moment- but what I take away from it is that there could be a very varied planetary zoo of tidally-locked and synchronous planets around red dwarfs, some of which seem likely to be more hospitable than others.
“Mind” means something - and it doesn’t mean “set of smaller minds who communicate with each other really well but don’t actually distribute cognition across all its bits”. At least it doesn’t to me.
And I’m talking about a hypothetical alien mind that does distribute cognition across all its bits. Such things don’t occur on earth, but it takes more dogmatism than I’m willing to countenance to declare, a priori, that such things cannot ever exist, anywhere.
Yes, I get that. I’m saying I can’t conceive of how that would work, and Vinge’s example doesn’t hold water.
It’s not *a priori *, it’s physics, which is universal. Spooky action at a distance on a macro level is physically impossible, not just on Earth, but anywhere.
Now, you’re right, it’s possible that unit-to-unit communication need not be instantaneous (e.g. sound) but like I said, that’s not shared cognition by any Mind model I hold, just improved communication. It’s not just a bandwidth issue, it’s a time and distance issue. Even comparing the bandwidth for sound to inter-hemisphere communication (which is by far the least part of cognition - witness split-brain individuals, who are still sentient beings), this misses out on the delay in timing between one mind processing something, then communicating it to the sound organ, then the transfer, then the reception and then the processing on the other side. Plus random noise and environmental losses.
This delay is orders of magnitudes over that in intra-hemisphere or even inter-hemisphere communication, and I don’t think can actually be characterised as a “Group Mind” any more than a flock of starlings has one.
E.O. Wilson discusses, “What aliens will look like and why”. Frankly, I find the discussion in this thread more illuminating than the linked article, but I thought I’d share anyway.
I’m always amazed that people can make such claims. We know literally nothing about 98% of the universe beyond the fact that it exists and has some gravitational effect. We are really that ignorant about how the universe is actually constructed. And the incompatibility of relativity and and quantum mechanics means that we are certain that our fundamental models of the universe are absolutely wrong.
Yet people still feel that they can make claims that certain things are absolutely impossible, in any part of the universe. That’s a hell of a claim to make based on models that we know are wrong about a universe of which we are 99% completely ignorant.
It’s one thing to claim that an object can’t exist in two places at once according to our best theories. It’s quite another to declare that it is physically impossible for an object can never exist in two places at once anywhere in the universe. Either of those statements could have been made in 1900. Only one of them has proven to be correct, and it’s not the one that seems like common sense.
That sort of thing is why I would be very reticent to declare in absolute terms that anything is impossible everywhere. The universe is far stranger than we give it credit for.
And of course, “spooky action at distance” needn’t be the mechanism for telepathy. Something as simple as radio transmitter/receiver could achieve a group mind that would be indistinguishable to all but the closest examination, and is not prohibited even by our current theories.
So your point is basically: “If we assume slow means of communication (e.g. sound), then…it would just be soo slow. Therefore hive minds ridiculous”.
Why not assume faster means of communication (e.g. EM radiation, which would be significantly faster than signals are propagated in the human brain)?
And why would being relatively slow rule it out as a thing that could exist anyway?
I’m not saying I’m expecting to encounter hive minds, I just don’t see your justification for throwing out the idea because “physics”.
I disagree - we’re really not that ignorant, not at the basic physics level. Stars and planets are made of the same base matter as on Earth. Unless you’re talking about energy beings, which, yeah, sure, maybe they’re telepathic. So when I’m talking about the impossibility of telepathy, I’m talking about it in physical creatures, like Earth life, but with a different body plan or radically different biology.
You could argue that physics may be different elsewhere, in which case it’s time to just throw our hands up and say “Fuck It! We can’t reliably say anything about the rest of the Universe!”.
Outside of singularities, physics is physics no matter where you go.
See, the way I see it, if it’s a Mind here linked to a Mind there, over even an EM channel, unless you postulate a different Theory of Mind, all you’re talking about is this Mind communicating with that Mind. It’s not distributed computing, it’s just networked computing, if you understand the difference. A biological Group Mind would require continuous, no-attenuation, two-way communication not just from the individual minds, but all the sub-units, to be considered an actual Group Mind, IMO.
No, I’m saying if the processing all happens in one mind, then gets communicated to another, that’s not the same as a group mind. What I’m saying is if you have a two-speed system, then the one speed is coognition and the other is … social cohesion or something. If you have a Group Mind that’s only working when the individuals are in the same room, that’s not what I’d call an actual Group Mind, it’s just some sort of pseudo-Mind
OK, to be more precise, I’m ruling out this sort of group mind for any human-like “animal” sentients. I think there’s timescales at which biological functions happen. Postulate energy beings or creatures that only live on neutron stars at 1/10000000 times our metabolism, and my objections go out the window.
The “physics” objection is only to the specific type of telepathy shown in most SF - mind-to-mind, no attenuation, no physical means of propagation.
Also, it isn’t demonstrated that sound is too slow. Vernor Vinge did the math, showing that sound could carry the same total amount (and overall speed) of information flow as the communication that exists between the hemispheres of the human brain. That’s obviously not too slow: it works to allow us to have “a mind” and not “two minds.”
Mr Dibble already provided an excellent response to this in post #76 just above, and I agree with him completely. You appear to be confusing the difference between incomplete knowledge and fundamentally incorrect knowledge, and stating that “… we are certain that our fundamental models of the universe are absolutely wrong” is nonsense.
We know, for instance, that the observable universe acts like it has a common origin, from which we can safely conclude that elements are therefore the same everywhere – this is very unlikely to be wrong, and has profound predictive implications for what can and cannot exist everywhere, including the nature of life. A hydrogen atom on earth is exactly the same as a hydrogen atom anywhere, and likewise for carbon and silicon and and everything else, and all the chemistry that might assemble them into the building blocks of life . To say that this might be completely wrong is baseless and not terribly useful or meaningful. Granted, we are likely to be very surprised by how life may have evolved elsewhere, but to suggest that the basic laws of physics may be completely different elsewhere is rather silly.
As for “spooky action at a distance” – i.e.- quantum entanglement – this is something that quantum physics describes that is completely different, and orthogonal to, anything predicted by relativity, but it doesn’t contradict it. Relativity describes a fundamental aspect of space-time in which simultaneity at different points in space does not exist in the intuitive sense but is a function of c, so nothing can be communicated faster than light. Quantum entanglement doesn’t contradict this because there’s no communication involved in the classic or meaningful sense of the word, nor could it ever possibly be used to communicate anything.