The assumption that biological life will be doing galactic colonization seems myopic in the extreme. Let's just consider the progression here. Life on Earth appears around 4.5 billion years ago. Humans start evolving around 2.8 million years ago. Use of language appears around 100,000 years ago. Writing is invented around 5500 years ago.
Inventions of language and writing are the landmark moment here. Before language was invented the only way information could be passed down from ancestors to offspring was via mutations in our DNA. If an individual learned some new idea it would be lost with them when they died. Language allowed humans to communicate ideas to future generations and start accumulating knowledge beyond what a single individual could hold in their head. Writing made this process even more efficient.
So, after millions of years of life on Earth no technological development happened. Then when language was invented humans started creating technology, and in a blink of an eye on cosmological scale we went from living in caves to visiting space in our rocket ships. It’s worth taking a moment to really appreciate just how fast our technology evolved once we were able to start accumulating knowledge using language and writing.
Now let’s take a look at how technology itself has been evolving. Once we discovered radio communication we went through a noisy period where we were leaking a lot of our broadcasts into space, and within a span of a 100 years we started using more efficient communication, and encryption. If somebody intercepted our broadcasts today they would look like noise because they’re designed to look like noise. Our society today is utterly and completely unrecognizable to somebody from even a 100 years ago. If we don’t go extinct, I imagine that in another thousand years future humans will be completely alien to us as well.
So the period during which intelligent life would be recognizable to us during its course of evolution is infinitesimally small. The time between creating language and becoming an advanced technological society is measured in thousands of years, while evolution of life is measured in millions of years. The chance of two different intelligences finding each other at exact same stage of development where they might be able to communicate is incredibly unlikely.
Based on that, I would imagine that the biological phase for intelligent life is rather short. We’re likely to develop human style AIs within a century, and they will be the ones to go out and explore the universe. Meat did not evolve to live in space, we’re adapted to gravity wells. An artificial life form could be engineered to thrive in space without ever needing to visit planets. This is the kind of life that’s most likely to be prolific in space. Furthermore, post biological intelligences would likely be running at much faster speeds than our mental processes operate on. What we consider real-time would be might we consider to be geological scales. Such beings might consider what we view as real time akin to the way we look at continental drift. We’re aware that it’s happening, but it’s of little interest to use on day to day basis. It’s quite possible that advanced civilizations become solipsistic and care little for the outside universe.
For all we know the Universe may be teeming with intelligent life and we just don’t recognize it as such. We might be like an ant hill next to a highway looking to see if there are other ant hills around.
> For all we know the Universe may be teeming with intelligent life and we just don’t recognize it as such.
This is my preferred answer to the Fermi question as well. Unless two civilisations are in a precise (and likely small) window where they both can and want to communicate, it's likely the less advanced one wouldn't even recognise the other one. Especially if the other one doesn't "want" to be recognised.
Yup, and just look at how difficult it is for us to recognize different kinds of intelligence on our own planet too. We've just started figuring out that animals like crows have complex cognition.
> Before language was invented the only way information could be passed down from ancestors to offspring was via mutations in our DNA.
Language (in the sense of "use of language appears around 100,000 years ago") is not the only way to communicate information, and many animal species are perfectly capable of communicating information despite not having evolved what is being called "language" in this sense.
The difference is that we are able to accumulate information across generations to grow our collective knowledge. Other animals are not able to do that at scale. So, while you are correct that other animal communicate and even teach each other, it's a qualitatively different situation from human communication.
We really don’t know this for certain at all. We do know crows can communicate information about the face of a person they dislike to their murder, including to new generations. It seems a bit of a stretch to say their cultural transmission is quite that narrow.
In general, pre-writing human oral culture seems to have dynamics much in common with such abilities in other animals. Barring error correction mechanisms, oral knowledge can degrade in transmission, limiting its reach and success.
This isn’t to say human language doesn’t have its distinctive features that are very useful. But the language came from a different brain, and is suited to the particularity of our brains. We should hesitate to place solely on language something that’s also driven by us having more things to say.
We kind of do though since we don't see crows accumulating knowledge at any scale comparable to humans and using this knowledge to shape their environment in increasingly complex ways. And crows very obviously do make tools and even teach each other to do it, so it's not like they don't have the inclination for it.
The language itself is a a human invention, and a product of how our brains are wired. However, there's a dialectical process here where the language shapes us in turn, and both our minds and our language evolve together. The reason we have more things to say stems from us accumulating knowledge and expanding out horizons through the use of our language.
But scale of knowledge acquisition is mediated by, at minimum, lifespan, and what knowledge there is to verbalize and pass on, no? It’s not like we got the language then built our hands based on the knowledge shared by another person with hands.
Instead, these co-evolved. Our language is shaped by that, and we shouldn’t give it too much causal power when it’s only a slice of the system.
We are also very unclear on what birds can communicate. They’re social migratory species with 4 color vision and magnetoreception. Their sensory context is deeper and richer in some ways, and whatever communication they layer atop it will be shaped by that. What seems like squeaks and chirps can hold information that another bird, but not humans, can decode. We’re getting better at layering all this context and then interpreting bird song and sounds.
But we’re at the beginning of this exercise, not a place where we can make a firm conclusion.
Sure, lifespan is a factor, but it's hard to argue that lifespan has been the main factor for humans. Or that lifetime of many other organisms isn't sufficient. And I already pointed out that we co-evolved with language, that's what it means for it to be a dialectical process. However, for language even get bootstrapped, it needs the prerequisite brain structures to support recursive grammars and abstractions we use.
What we can look at is what other species are able to accomplish and how much they are able to shape their environment. I'm not arguing the fact that we don't have a good grasp on how other animal communicate and different kinds of intelligence we have in the animal kingdom. What I'm saying is that our unique combination of being able to abstract concepts and package them up using language, and especially writing, is what allowed up to rapidly accumulate knowledge and pass it across generations. We are demonstrably the only species that does this. Although, there were other hominids originally with similar capabilities that went extinct.
They're not saying humans don't have profound communication advantages. Obviously the crows don't have nuclear generators and spacecraft. They're saying that the categorical claims about why humans have profound advantages aren't correct.
The fact that we are able to accumulate knowledge and apply it to shape our environment in a way that no other species is able to kind of does suggest that we have a profound communication advantage.
Everybody here agrees that we do.
I’m thinking along my similar lines. Expansion, if it happens, will likely not be on a recognizably human substrate, but rather something else. But currently it’s more of an intuition than a rigorous argument for me. How do would you formulate a more solid argument around this idea?
Against Mind-Blindness: Recognizing and Communicating with Diverse Intelligences - King's College London Neuropsychiatry Research & Education Group - https://www.youtube.com/watch?v=RHkFmUwW0kM
Sure, intelligence is a gradient, it's not something exclusive to humans. And different biological systems need to solve problems and create models of their environment in order to respond to it intentionally. However, that's tangential to the point I was making, which was that we are able to rapidly accumulate knowledge across generations giving us mastery of our environment that's qualitatively different from any other organism on the planet. And the next logical step here is machine intelligence where human style intellect could be implemented on a non-biological substrate which would open up completely new niches for postbiological life to inhabit.