Also, if you do become the xenocidal aliens, a coalition of survivors from various species might team up to xenocide you right back.
Acting aggressively or boldly exploring equally so. If you believe there are others then trying to stay below the radar building defensive capabilities is the wisest choice.
Acting aggressively, yes, boldly exploring, I would still say no.
Let’s say there’s a species that’s broadcasting greeting messages, and boldly trekking around the galaxy. Call them X.
Now, some species might not like that; they might consider X a possible threat.
But attacking is risky.
A species weaker than X, should of course be reluctant to preemptively start a war which could be the very thing that would wipe them out.
A species much stronger than X, but still afraid of potentially yet stronger species, would feel that wiping out X would be wiping out something that’s not a threat right now and potentially drawing the attention of species that are. Furthermore, since X boldly explores the galaxy, they may well have been noticed by many species, plus you’ve got to blow up more colonies, ships etc to exterminate them, and so the risk factor of attacking a trekking species is much larger than attacking a hermit species.
Then, we come to the case of a hypothetical species that considers themselves the most advanced, and yet still wants to trample out other sentient species. This species has no reason to passively wait for sentient species to make themselves known; they can install probes around every star system.
The only case where a preemptive attack might be justified (under this logic) is if a species is at a comparable level of technology as X, but feel X is advancing quicker than they are. But this is an extremely improbable scenario given the age of the galaxy.
And the point about it attracting the attention of bigger species, loudly announcing themselves as an aggressor species still applies.
So, all together, I don’t think the logic that exploring puts one more at risk due to the Dark Forest hypothesis actually works on analysis. In terms of existential attacks, it may actually make a species more safe.
Other than that we most likely won’t be around to have that conversation by that time, so may as well have it now. 
I can’t say I disagree, but I reserve the right to change my mind if and when we actually get the capability.
So, that’s another argument against the idea that civs are out there, hiding. Not only can we make the assumption that we are not hidden, but we can also make the assumption that, even if we were not hidden, then no one would want to wipe us out.
But, this is all based on the info that we currently have. What happens if, when our next generation, or the generation after that, space telescopes come online, and looking out, we see clear evidence of stars being used to power interstellar lasers and worlds that have been burnt to a crisp?
Do we still try to hide, or do we try to fight back?
Downside of exploring is drawing the wrong kind of attention.
If we are just sending probes through other solar system to see what’s there, then maybe no big deal.
But if we start using Von Neumann self replicating probes, someone may get offended over us using their resources.
We may not even recognize that there is life on a world, much less intelligence, if it is alien enough to us. Perhaps they are super intelligent, but also fairly sedentary, and have no use or desire for expansion into space. That is until some piece of alien kit lands on their world and starts mining it in order to replicate itself.
I can see a situation where Von Neumann machines basically become a galactic disease, infecting and ruining worlds and solar systems. At a certain point, a civ may want to start going right to the source of these infections.
One of the campaign settings that I used for an RPG was a bit like that. The backdrop of the galaxy’s history was that a pacifist civ kept getting “attacked” by these self replicating probes, and had a hell of a time trying to contain them. Ended up not sterilizing worlds, but containing them. Tossing gravel balls into their solar systems to create essentially a solar system wide kessler syndrome, discouraging space travel, but still allowing life to develop more or less normally on the planet.
Bit of a form of the “zoo hypothesis” I hadn’t seen before. Not that there is a wide ranging conspiracy to prevent alien cultures from contacting us, but just that they have put up “bars” around all the planets that could be life bearing.
Well, we’d be truly and royally fucked, in that case. Maybe we could build a secret bunker in the deepest part of Earth’s crust, and hope the aliens only scorch the surface rather than melt the crust completely.
Burning to another star is out of the question - the aliens would definitely spot our engines, if they’re already in the process of wiping out other worlds. But maybe we could go to the moon while they’re not watching (or only burn when the moon is between us and them, but they likely have listening outposts across a wide range of the sky, if they’re burning other worlds already). The moon is geologically dead, so we could dig all the way to its core to build our hiding hole. And maybe the aliens won’t blow up the moon, since it’s clearly home to no life at all.
Yes, this.
In science fiction, alien species are usually technologically comparable. Even in stories where one species is supposed to be dominant, the lesser species will still win victories from time to time, or ultimately.
The reality is, the technological gap between two random intelligent species is likely to be thousands of times bigger than all of human history combined.
Physics will limit how “godlike” a species could ultimately become. But the idea that a species at the lowest rung of interstellar technology, as humans would be, could realistically fight back against a species that has been interstellar for millions of years, is laughable. We’d be screwed in ways we can’t imagine.
Yes absolutely. Throwing out replicating probes would be an incredibly irresponsible action, both from a personal safety as well as ethical POV.
I put “ethics” to one side earlier, because I wanted to focus on addressing the Dark Forest hypothesis. But, bringing it back in, I think humans should be careful about unrestricted mining while we don’t know how many species are out there, or if those probes could be a threat to ourselves later. And, personally, I don’t give a shit about the preservation of our species versus other sentient life – just because I am a human, doesn’t mean I subscribe to a “Humans First” philosophy.
If humans want to be considered more valuable that other sentient species, I want to hear a supporting argument for that.
This is very true. Unless these probes are able to replicate PERFECTLY every single time, you’ve introduced mutation into the equation, and therefore evolution. Once natural selection is acting on them, you don’t have any control on the final outcome. Probe lineages will diverge, diversify, and compete with each other (and those probes that don’t do this will be outcompeted by those that do). It isn’t hard to imagine that something may go horribly wrong.
Good point. I didn’t even think of the mutation possibility, and self replicating probes are an extremely reckless idea even without that.
It makes me wonder if there are not solutions to the Fermi paradox associated with that…
Because, even if governments realize the folly of self-replicating probes, they are likely to be cheap enough to make that any small faction or even individual can launch them.
Given that reality, how does that affect the strategy of a species trying to live and prosper within this galaxy?
Answer: I don’t know at all, just thinking out loud.
The problem with that is that the Fermi paradox asks why we don’t see signs of aliens - it doesn’t matter if the aliens we aren’t seeing are naturally evolved critters, or runaway replicating drones.
If an ancient alien civ halfway across the galaxy created Von Neumann Probes twenty million years ago and those probes went rogue and wiped them out, wouldn’t those replicating probes have the same resource acquisition drive that we expect biological species to have? Therefore wouldn’t we expect to see their impact as they spread from star to star, harvesting its energy, and shifting its emissions from the normal star spectrum to infrared waste heat?
It would only take one irresponsible alien scientist to build a Von Neumann probe and send it to the next star system over to kick off a runaway process that should wash over the galaxy in millions of years, or the equivalent of the blink of an eye in the timescale we are discussing.
No, you misunderstand me.
I’m not suggesting that for the purposes of Fermi’s paradox that there’s any qualitative difference between whole species embarking on such projects versus small groups, far from it.
The fact is, we don’t see such probes, and probably the simplest candidate answer is that no species has been in position to make such probes, due to some kind of “filter” prior to the stage humans are already at.
But, allowing my imagination to really run, I wonder if another answer is that the means to prevent such probes from running amok is the same as the reason the galaxy looks sterile. Of course, this would involve tech way beyond our physical understanding right now, so it’s an utterly pointless (but interesting, to me) thing to speculate about.
As I was typing my prior message, I had a thought.
There’s a theory that large animals like elephants and whales are resistant to cancer, despite having many many times the number of cells (and therefore cell division events and therefore chances for a cancer to begin), because even though cancerous tumors are still likely to form in their bodies, a tumor is inherently unstable, due to the specific set of mutations required for cancerous cells to grow out of control. So in a large animal, a tumor needs to grow fairly big before can kill the animal, and it simply isn’t likely to last long enough before acquiring new, additional mutations, that cause the cancer to compete with itself and starve for resources.
Maybe mutating self replicating probes can grow out of control, but before they become galaxy-spanning, they tend to mutate, compete with the unmutated probes, and die off.
How about non-sentient life? If we find a world full of algae, is that fair game? If it has more complex life, but no animals? If it has animals, but nothing too advanced?
And that is assuming of course that we recognize life and sentience when we see it. There could be a sentient civilization based on the crystallization of minerals in an asteroid in our solar system that we go out and genocide without ever even knowing it.
That’s actually quite doable. There are several ways, but the easiest would be to just have a couple dozen copies of the code and blueprints, and compare them before replication comences.
It would not be hard to get a system robust enough that it has only a one in quadrillion chance of one of quintillions of probes has a single bit changed in the next 10^100 years. Much less any significant amount of code.
Life mutates because it started off as a mutation of non-life, and mutation is beneficial to increase its growth and spread. There is no reason why we need to make artificial systems capable of the same.
There are many considerations that need to be made, before polluting the galaxy with our junk, but the mutation aspect is one that we really can control.
The Elon Musk of the 23rd century almost certainly will, if not sooner.
At the end of the day, what’s the difference between a Von Neumann probe, and a species itself spreading out, colonizing, and exploiting the resources of the galaxy?
Or starlifting them into red dwarfs. Some look into the sky and see brilliant diamonds of light, I see burning oil wells.
If we achieve personal immortality, then suddenly, the idea of the heat death of the universe stops being an academic issue, and starts being one that will affect you. Just as we are supposed to save for retirement, we need to save the energy these stars are squandering.
It would be perfectly reasonable for an alien species to send probes out to self replicate, and start turning the stars off. Which of course may be annoying to anyone who was currently using that star to warm their planet.
Yeah, I’ve given that some thought. Every second that a star twinkles, you’re wasting millions of years worth of fusion products that could be used to power super efficient computers on which entire societies live at the end of time. From that perspective, it’s almost irresponsible NOT TO fly to every star and halt fusion ASAP so we can drag the hydrogen and helium back home to use up over the next few trillion years.
Also, anything that slips over the edge of the observable universe is lost forever and completely wasted. We’d need to do some triage and figure out what we can get to in time to stop it from disappearing over the horizon, and what we could bring back to a usable distance without wasting more energy than we’d gain.
And, since it would be rude to do that to anyone using that star, then if we come across life while we are “optimizing” the universe, you give them an upgrade to a state of the art simulation in your computer systems.
I don’t know how much energy it would take to run a full scale simulation of the Earth and everything on it, but it would probably be far less than the sun is putting out, so a net win right there. Not to mention the stars in the sky that are just completely wasted.
So, that comes back around to the Zoo hypothosis by way of the Simulation hypothosis. We are being “preserved” and allowed to grow and develop within the Matrix as a more efficient energy usage method.
Of course, there’s no way to know from the inside of such a simulation whether this is the case or not, so we may as well operate under the assumption that it is not. If we try to leave the solar system and run into an invisible wall, we will know we were in a simulation!
(There would have to be some limit eventually, because if you modeled the whole universe, you’d eventually use up more energy than you’re saving…)
(Of course, we’d have no reason to believe the outside universe follows the same laws of physics as our simulation. So maybe that doesn’t follow…)
When we try to leave the solar system, that’s when they tell us.
“Hey, you know how you were all worried about all that wasted starlight, and you were thinking about going out and turning off all the stars? Yeah… we already did that, you’re welcome.”
Probably, but it depends on how robust that model it. We may simply be programmed not to notice holes in it. No one actually looks through a telescope anymore, certainly not for anything deep. Be trivial to just have the things that we expect to see show up on our screens.
Assuming that the simulation is intended to allow a planet’s ecology to continue to develop and grow, then it would stand to reason that the simulation would resemble the universe it was taken from as closely as is practicable.
Reading this thread, I have learned two things:
- Aliens are smarter and have more self-control than we do.
(or, they’re too far away to have even noticed us at all…)
- The OP hasn’t learned from the education he got (or could have gotten) from his other threads.
Watch Isaac Arthur on Youtube if you want to explore this in detail. The guy is great. He has a whole series on the Fermi Paradox (and many other topics as well).
He also thinks the Zoo Hypothesis is unlikely. His ‘gut feeling’ is that multicellular life is very rare or intelligent AND technological civilizations are very rare. However, he explores them all in detail. He isn’t known for short videos 
Ancient Astronaut theory is scientific, imo. It’s just that there is zero credible evidence for it. Just because an idea is wrong doesn’t make it not scientific. Just a failed hypothesis. 