1

"The theory that we’re either the first form of intelligent life or the last"

2

"The dual consciousness theory disturbed me when I read about it.

Basically (in my limited, layman understanding), a corpus callosotomy is a procedure that is sometimes used to treat conditions like epilepsy, where the connection between the two halves of the brain is severed. People can survive this and continue to live semi-normally, but usually with some cognitive impairments. Both halves of the brain continue to be ‘alive’, but there is little to no communication between the two sides.

People who undergo the procedure can also exhibit some strange phenomena like alien hand syndrome, where the patient feels like some of their limbs will move on their own accord. They can also have difficulty controlling their non-dominant hand, trouble speaking, and issues with certain parts of their vision.

The dual consciousness theory posits that both halves of the brain retain consciousness after this procedure. Essentially, you become two people sharing the same body, completely unaware of each other. One variation of the theory is that one half of the brain is dominant, controlling most bodily functions, while the other half is basically cut off from most external stimuli, unable to communicate with the outside world, for the rest of their life."

3

"The great filter. The idea that we see no other civilizations out in space because they hit some wall that made them go extinct. Whatever it may be, it could be the reason we see no intelligent life out there, the question is, are we past the filter, or is the worst still to come?"

4

"The dark forest theory, that there are lots of other advanced civilizations out there in space, but they’re concealing their presence because they know how suicidally dangerous it is to be broadcasting your planet’s location out to the universe."

5

"I heard on another thread about “what would be the scariest thing found at the bottom of Mariana’s trench” and someone said “the top of a skyscraper”"

6

"That at any moment at any given time some unknown cosmic thing could come from outer space and wipe us out in a blink (ie. Vacuum decay or Gamma ray burst). Even our Sun could just produce a huge enough solar storm and we are basically doomed"

7

"The theory that f@#ks with me the most is that space is infinite. I can’t wrap my head around the idea of something having no boundary or end and it creeps me out that it’s possible"

8

"Quantum immortality. If correct, it guarantees that you will never die. It guarantees nothing else."

9

"That theory that you’re a b#tch if you make two trips to carry in your groceries."

10

"The theory of proton decay, where every single bit of baryonic matter will eventually just spontaneously dissolve into radiation and fundamental particles, guaranteeing that there will be no survivors at the end of the universe is… yeah terrible"

11

"That a more stable form of vacuum exists and if it did, we would collapse into it. It could be headed towards us now and we literally would never know it’s coming."

12

"The idea that the Uncanny Valley is because of the ancient hominins we used to interact with during the Pleistocene. Sure, there were interbreeding events, but imagine if you had no idea what a Neanderthal or a Denisovan were and saw one for the first time.

You and your family have been traveling far from home and seek refuge in a cave for the night. You get a fire going, everyone starts to relax. Then out of nowhere, this “almost human” looking being walks up. You all panic and run. Reacting with fear was probably the easiest way to make it out of an encounter like that alive."

13

"Cold Death of the universe. That the speed at which the universe is expanding is to the point where gravity will never pull it back. Matter will spread out and cool down and decay until everything, everywhere, just stops. forever."

14

"Solipsism. Basically, There’s no way to prove that anyone other than yourself actually exists. You can dive deeper if you like it’s actually pretty interesting."

15

"The fact that it would take 8 minutes for earth to know that the sun exploded and it could have exploded 7 minutes ago"

16

"That our consciousness doesn’t actually direct our actions, but just makes up stories to explain our actions to itself. Consciousness might not even be useful to our evolution, it could just be a weird phenomenon that came about as our brains became more complex and developed more self-monitoring systems."

17

"Not really a theory but being the oldest person alive. There’s just something so chilling about the fact that literally every human that existed at the time of her birth is now dead except for her. She’s the last of the human race in her snapshot of time."

18

"Eternal Recurrence suggests that this universe will be reborn again over and over endlessly, and so we will also be forced to relive the same life just as many times.

Take a moment to consider your odds of being here, now, with infinite time before and after you."

19

"If you get blasted with a ton of radiation, your body instantly dies. But you will keep living for a while. Potentially weeks, like the Japanese nuclear plant worker who took more radiation than anyone else in history. Your DNA will shatter throughout your body, meaning as cells die, they will never be replaced again. Your body essentially starts rotting while you’re still using it."

20

"Potential answer to the Fermi Paradox: we’ve never seen evidence of an alien civilization because no intelligent life survives long after the discovery of nuclear weapons."

21

“Let’s say intelligence is your ability to compose poetry, symphonies, do art, math and science. Chimps can’t do any of that, yet we share 99 percent DNA. Everything that we are, that distinguishes us from chimps, emerges from that one-percent difference.”

“Imagine a life-form whose brainpower is to ours as ours is to a chimpanzee’s. To such a species, our highest mental achievements would be trivial. Their toddlers, instead of learning their ABCs on Sesame Street, would learn multivariable calculus on Boolean Boulevard. Our most complex theorems, our deepest philosophies, the cherished works of our most creative artists, would be projects their schoolkids bring home for Mom and Dad to display on the refrigerator door.”