History WebVideo / IsaacArthur

* ArtificialGravity: In his episode on [[https://www.youtube.com/watch?v=M8ryqjyLBL8&list=PLIIOUpOge0LvT-g_LNsfX_2ld0pn-CDSZ megastructures in space]], Isaac discusses how space stations of the future might generate this via centrifugal force.

* AncientAliens: Discussed in [[https://www.youtube.com/watch?v=0yyQpTaxKL8 Ancient Aliens]].
* {{Arcology}}: [[https://www.youtube.com/watch?v=TqKQ94DtS54 Discussed here.]]

* HumanPopsicle: In [[https://www.youtube.com/watch?v=fM-JHvg-ZCM Sleeper Ships.]]
* HumansAreSpecial: Isaac has a very positive view of humanity's future and capabilities, and [[HumansAreFlawed while agrees that we're not perfect]], he's not too clear why so many people are down on humanity. In fact, in [[https://www.youtube.com/watch?v=aDqjK5vR6hE "Stay at Home Civilizations"]], he says that we ''should'' be examining ourselves and finding faults whenever we can. If we weren't, we'd be a species of narcissists who shouldn't be leaving the planet at all.
** Isaac has also admitted that he feels humanity may be an anomaly in the universe and that we're actually the first civilization to emerge.

* ScifiWritersHaveNoSenseOfScale: Frequently discussed and gives ideas on how to avert it.
* StarfishAliens

* RunningGag: See RuleNumberOne below.

* AlmightyIdiot: In "Crazy Aliens", Isaac touches on the concept of an EldritchAbomination and how it doesn't seem like a particularly realistic product of evolution. Instead, it seems more likely to be the product of ''genuine'' insanity, like a superintelligent AI that stews in its thoughts for so long that it determines life is meaningless and free will is an illusion, snaps and becomes a [[StrawNihilist nihilistic]] OmnicidalManiac as a way to invent a purpose for itself.

* FoldThePageFoldTheSpace: Discussed in "Folding Space", where he explains that this analogy is better applied to the concept of folding spacetime, moving two destinations together through a higher dimension, itself rather than wormholes. And if any higher dimensions do exist, it may be the ''best'' candidate for faster-than-light travel.

* ArbitrarySkepticism: Isaac has joked more than once that some of the concepts he discusses at length, such as Solar System-spanning megastructures or life extension, both of which are completely doable under known physics, somehow seem less plausible to people than FTLTravel, which is likely mathematically impossible.

* FasterThanLightTravel: Isaac does not believe this is possible, but that hasn't stopped him [[https://www.youtube.com/watch?v=yCCsmxGjEV0 from]] [[https://www.youtube.com/watch?v=LNwhe_ztaGw discussing]] [[https://www.youtube.com/watch?v=2_4l5_G3dnM it.]]

* Lightworlder: Subverted in his episode "[[https://www.youtube.com/watch?v=CBLCNWpLFBg Life on a Low-Gravity Planet]]," where he speculates that such life could actually grow bigger and stronger than life on Earth.

** Also on the list are HumungousMecha. He admits the technology to build them is plausible, and it would actually make sense to not only build them to look humanoid for convenience, but also to fight using swords to avoid collateral damage. The problem is that you'd never get the chance to swing a sword, since your opponent will likely be using projectiles, and if you'd be willing to have a duel like that, you could just do so in virtual reality. He does suggest possible reasons why you'd have human-shaped mecha are people agreeing to real duels in them, flooding a battlefield with them as a combat tactic, and it's easier to armor them if they're bigger. While they're not as efficient as smaller war machines, he does admit people may build them [[RuleOfCool simply because they're cool]].

** The Dark Forest Solution to the Fermi Paradox, where all alien civilizations view others as existential threats, suggests the universe is quiet because they're either all hiding or dead, as anyone who makes themselves known gets taken out quickly. Isaac considers this easy to debunk: anyone who chooses to attack also reveals ''themselves'', since it's impossible to hide in space, and thus making an aggressive action like that shows ''you're'' the biggest hostile force around and [[EnemyMine it may drive everyone else to gang up on you]]. In addition, Isaac doesn't see any reason why civilizations ''would'' immediately view each other as existential threats otherwise.
** Isaac considers the biggest nail in the Dark Forest Solution's coffin to be the fact that, while we've only been broadcasting into space for about a century, the signs of life on Earth have been present for billions of years. If a species truly wanted to destroy any civilizations that could pose a threat, they would either sterilize every life-bearing planet they could detect or they'd simply colonize them to prevent another civilization from arising. In short, if this were true, we likely wouldn't even exist in the first place.

* LivingForeverIsAwesome: While Isaac points out some issues immortality could cause, he ultimately sees nothing wrong with living forever and doesn't believe he would ever get bored with life, even if he got to live for millenia.

* RobotWar: Played with and often subverted. While he usually advocates for keeping them simple and dumb, Arthur sees no reason why truly intelligent machines would immediately see humans in particular or organic life as a whole as a threat or otherwise decide to destroy us.

** He also considers artificial planets in general to be this trope when compared to rotating habitats and feels disc-shaped artficial planets are less practical than shell-shaped ones, though his opinion on this has shifted over the years. In [[https://www.youtube.com/watch?v=U2bc7kZcpmQ his original video on disc-worlds]], he argues they would provide less living space than a shell-world of the same radius. In [[https://www.youtube.com/watch?v=JGu-DYTYzzE his later video revisiting them]], he makes the same argument, but he does note that their [[SingleBiomePlanet uniform climate]] could make them attractive tourist spots and that an advanced civilization collecting entire solar masses of fuel for fusion could store the matter in discs or sphere and then add land and seas so that they double as living space.

* MohsScaleOfScienceFictionHardness: Isaac mostly talks about technologies that fall under category 5 (Speculative Science) or 5.5 (Futurology), which are at least theoretically possible under known physics. For example, many [[BrainUploading simulated minds]] could be run using just a few watts of power at very low temperatures according to the [[https://en.wikipedia.org/wiki/Landauer%27s_principle Landauer limit]], but current computers are not that efficient yet.

* AwesomeButImpractical: His opinion of the [[https://en.wikipedia.org/wiki/Alderson_disk Alderson disk]], since, as he points out, they would buckle due to gravity and have no light, and the commonly suggested "solution" of a having a sun bob up and down in the middle is pretty much impossible under the laws of physics. He does, however, suggest some ways to make it more practical, such as having massive mirrors reflect light onto the disk and building the disc on special support structures. He also considers the entire concept of disc-shaped artificial planets to be this trope in general compared to shell-shaped ones, since they're not as mass-efficient, though not by much.

* AwesomeButImpractical: His opinion of the [[https://en.wikipedia.org/wiki/Alderson_disk Alderson disk]], since, as he points out, they would buckle due to gravity and have no light, and the commonly suggested "solution" of a having a sun bob up and down in the middle is pretty much impossible under the laws of physics. He does, however, suggest some ways to make it more impractical, such as having massive mirrors reflect light onto the disk and building the disc on special support structures. He also considers the entire concept of disc-shaped artificial planets to be this trope in general compared to shell-shaped ones, since they're not as mass-efficient, though not by much.

"Or in short form, welcome to SFIA, where we´ll cheerfully discuss how to use hydrogen bombs to save the environment"
— Isaac Arthur, "Climate Change Mitigation: Near Term Solutions"

* MohsScaleOfScienceFictionHardness: Isaac mostly talks about technologies that fall under category 5 (Speculative Science) or 5.5 (Futurology), which are at least theoretically possible under known physics. For example, many [[BrainUploading simulated minds]] could be run using just a few watts of power according to the [[https://en.wikipedia.org/wiki/Landauer%27s_principle Landauer limit]], but current computers are not that efficient yet.

* TechnologyLevels: In [[https://www.youtube.com/watch?v=dArpj_VxxuQ this video]] about the [[JustForFun/AbusingTheKardashevScaleForFunAndProfit Kardashev Scale]], Isaac mentions how a Kardashev Type II civilization (which harnesses all the energy of its parent star) would be unthinkably bigger than anything we think of today, even counting many science fiction franchises: