1. How much dogs love us. There is no way we’ve been good enough boys/girls/humans to deserve this.

2. Popcorn. It’s freakily amazing that corn kernels turn into this stuff. And as a bonus, it’s delicious.

3. That humans, working together, eradicated the last wild strain of smallpox in the 1970s.

This was a mind-blowingly huge win for our species. It had plagued us since ~3rd century BCE and is estimated to have killed ~500 million people just during the last 100 years it was around.

4. That we have three types of color receptors. This allows most people to see an AMAZING array of colors!

Cats and dogs can’t do this, and things must look way duller.

However, colors probably are way cooler to birds, some of whom have FOUR color receptors and can see ultraviolets!

5. That we freaking EXIST! Think about that for a moment. Almost every human that has ever lived is not alive right now, but you and I are!

It seems to be crazy luck that we were born at all. If your parents had sex moments later, a different baby likely would have been born, as a different sperm likely would have fertilized the egg (or none would have at all). As  A.J. Jacobs points out, with an average of hundreds of millions of sperm per ejaculate, these odds are like winning a major Powerball lottery!

6. That we’re not chickens (or insects)!

Probabilistically speaking, shouldn’t we expect to be a member of the most abundant category of conscious beings on Earth rather than a rarer category?

If chickens are conscious (as I think they are), we really lucked out to be born human instead of one of the >20 billion chickens alive right now that’s living in terrible factory farm conditions (and that will die as soon as it is big enough or isn’t laying enough eggs).

If insects are conscious (have something that it’s like to be them, which might be true for some insect species, though I doubt it is true for all of them), then it’s REALLY weird we don’t find ourselves to be insects since there are vastly more of them than humans!

7. That any conscious beings exist at all! Why isn’t the universe just a bunch of gas and rocks and shit? It’s not at all obvious there should be anything that has the ability to have experiences – yet here we are!

It’s not even obvious why there is SOMETHING instead of NOTHING!

This was first written on February 19, 2021, and first appeared on this site on November 25, 2022.

Below is my list of what I see as the deepest mysteries. 

What would you add to the list?

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LIST OF DEEP MYSTERIES ABOUT THE NATURE OF REALITY

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1. THE UNIVERSE

1.1 Eternity – Will our universe last forever? If it won’t, what will the end of the universe be like (e.g., a new big bang, a big crunch, time simply ending, something else)?

1.2 Genesis – Did our universe have a “starting point” (in a pre-existing expanse of time) or has it existed forever, or did time begin when the universe began?

1.3 Geometry – Does the universe extend infinitely in all directions, or is it finite? (To get a feel for how it might be finite without requiring a boundary, consider that the universe could be like the game Pac-Man, topologically – in the sense that, traveling long enough in any direction, you eventually get back to where you started). Is empty space perfectly flat (e.g., like an infinite plane but in multiple dimensions), or does the universe have implicit curvature (e.g., like the surface of a universe-sized orange)?

1.4 Constraints – Could the laws of physics be any different than they are, or is there some reason they have to be this way? Why are there the particular elementary particle types that we find (e.g. electrons, quarks, neutrinos, etc.) with the particular properties they have? Why are there the particular forces we find (e.g. electromagnetism, gravity, the strong nuclear force, etc.) with the particular properties they have?

1.5 Entropy – Why was our universe in a low entropy state in the distant past (with the matter fairly uniformly spread out, rather than, for example, all condensed into black holes)?

1.6 Reason – What’s the right explanation for WHY our universe came to exist? If it was not created by any form of intelligence, is the question even coherent to ask? If it was created by some form of intelligence, was it God, or some other form of intelligent beings (e.g. aliens creating a universe simulation in some vast computer)? If there was an intelligent creator, what is the nature of that creator (e.g. what is that creator like, what does that creator care about, etc.)?

1.7 Uniqueness – Are there other universes besides our own?

1.8 Travel – Are wormholes (connecting different parts of spacetime) actually possible? Is time travel forbidden by the laws of physics? Is instant teleportation impossible?

1.9 Dimensionality – How many dimensions of spacetime are there? (e.g., the standard view is four dimensions, which come from three spatial dimensions and a single time dimension, whereas ‘string theory’ suggests more, though most of those extra dimensions are believed to be really tiny/compact)

1.10 Computability – Can the universe be simulated to arbitrary accuracy on a normal computer (given sufficiently large amounts of memory and time), or is there something “incomputable” about the universe?

1.11 Expansion – Why does the universe seem to be expanding at an accelerating rate? If dark energy exists (the hypothesized element that is believed to make up most of the energy of the universe, not to be confused with dark matter), then what is it and why is it there?

1.12 Dark Matter – Does dark matter actually exist (i.e., the hard to detect element that appears to make up most of the mass in the universe)? If so, what is it made of?

1.13 Unification – How can general relativity and quantum mechanics be combined into a consistent theory that generalizes both (e.g., to model what happens when extremely tiny things are in strong gravitational fields)? Is ‘string theory’ the right path towards unifying general relativity and quantum mechanics (as many physicists believe), or is it a misguided approach (as a few physicists argue)?

1.14 Energy – Is there a positive, zero, or negative total amount of energy in the universe?

1.15 Divisibility – Are space and time infinitely divisible, or are there truly minimum lengths and durations?

1.16 Aliens – Does intelligent life (or even non-intelligent life) exist elsewhere in the universe? If intelligent life does exist elsewhere in the universe, why does it appear not to have reached us yet? Will we ever encounter life that has non-earth origins?

1.17 Life – Why does our universe have a set of physical laws and physical constants that allow for life (and consciousness) to exist at all? Some people argue that if the strengths of the basic forces of physics (like gravity) had been more than a certain increment stronger, or more than a certain increment weaker, life could not have formed in our universe.

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2. HUMANITY

2.1 Origin – What were the first “replicating entities” that all the humans today eventually developed from? Many religions say that God placed the first humans here, who eventually gave birth to all the others. But as for non-religious (evolutionary) explanations, there are various theories about what these replicating entities might have been (e.g., crystals, or special molecules that can make other molecules they bump into look like themselves)

2.2 Extinction – When will humanity go extinct? And what will cause humanity’s extinction?

2.3 Governance – Given the flaws and limitations of our species, and our current state of technology, what systems of governance, laws, and institutions would maximize human flourishing?

2.4 Happiness – Given the current state of the world, and the nature of and resources of one particular person, if that person wants to maximize their happiness, what should they do? What would a supremely intelligent being tell a human about how to become happier?

2.5 Qualia – Do humans have different internal experiences in cases where we typically assume them to have the same experience? For example, do there exist non-visually impaired people whose internal experiences of red (e.g., when looking at a red apple) are totally different than each other? For instance, could it be that one person’s experience of red is what another person experiences as blue? Or even that one person experiences reds as being somewhat more like what someone else experiences for blue things?

2.6 Humor – Why do humans have humor? There are many theories (e.g., “benign violation theory” and “superiority theory”) but none of them seem complete/comprehensive.

2.7 Music – Why do humans love music so much? It’s hard to understand this from an evolutionary perspective.

2.8 Yawning – Why do we yawn? And why are yawns contagious (i.e., seeing someone yawning tends to make others yawn)? There are various theories (e.g., to cool down the brain, or to get more oxygen). My preferred highly speculative explanation is that it’s a mechanism for groups to sync their sleeping, but it’s really hard to know if that’s right.

2.9 Nutrition – What should we do to not merely stave off malnutrition, but to thrive and be as healthy as possible? There seems to be a disturbing lack of consensus on this question (and it may turn out to depend a lot on individual people’s genetic and behavioral differences).

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3. KNOWLEDGE

3.1 Induction – is there a sound argument in favor of using induction that is non-circular (i.e., that doesn’t implicitly rely on using induction to make the argument)?

3.2 Occam’s Razor – Is there a sound justification for Occam’s razor (by which I mean the claim that “simpler” explanations are more likely to be true). If so, what’s the right notion of simpleness for a hypothesis that doesn’t require making arbitrary choices (e.g., avoiding the issue Kolmogorov complexity has where it introduces an arbitrary choice of representation language)?

3.3 Cognition – What algorithms are human brains running that allow humans to learn, remember, model the future, model other minds, reason, plan, theorize, and make inferences? Is it possible to build something broadly as smart as (or much smarter than) a human using just incremental improvements on top of today’s deep learning algorithms (combined with larger data sets and faster computation)?

3.4 Infinities – How should we think about maximizing the expected value of an action in contexts where we can’t assign strictly zero probability to outcomes of infinite value? The mere possibility (i.e. non-zero probability) of an infinite value seems to mess up the calculations completely. If we’re trying to maximize expected value, how do we resolve “pascal’s wager” and “pascal’s mugging” type situations?

3.5 Priors – How can we assign prior probabilities to hypotheses in a principled, computable way (that is, how do we decide what probabilities to assign to hypotheses BEFORE we are given evidence to use to update those prior probabilities)?

3.6 Anthropics – How do we perform reasoning and probabilistic estimation in “anthropic” scenarios where we are forced to consider the probability of even being the sort of mind that could end up in that scenario? What’s the right way to think about questions like “what’s the probability that I would end up being me rather than someone else?” or “what’s the probability that I would end up being a human rather than another species?” or “what’s the probability that I would end up being one of the last 1 billion people to be born before humanity goes extinct?”

3.7 Reference Classes – If we have multiple categories something falls into (each implying that we make different predictions about that things), how do we combine this information into a final prediction? For instance, if ALL we know is that X is a flying car, and flying machines rarely have property Y, yet cars usually have property Y, how do we make a principled “best” estimate of the chance that X has property Y? In other words, what’s the right way to think about combining the information Prob( Y, given A ) with Prob( Y, given B ) when what we really need to know is Prob ( Y, given A and B )?

3.8 Black swans – How do we probabilistically model situations (or do expected value calculations) when we know that “black swan” events (that are unlike any we have seen in the past) are possible, even though we don’t (by definition) know what these events will actually be like and how likely they are to occur?

3.9 Consciousness – Can we be 100% certain that some form of consciousness exists (because we have direct perception of conscious experiences), or should we be less than totally certain even about this?

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4. EXISTENCE

4.1 Many Worlds – Are the “many worlds” of quantum mechanics actually all literally existing (i.e., are they as real as what we all are experiencing right now)? Or does the mathematics just make it seem that way? If they are not really there, what’s the resolution to the “measurement problem” in quantum mechanics (e.g., how do we define what a measurement is and is not such that we have a complete description of when quantum wave functions collapse)?

4.2 Anything – Why does “something” exist, rather than there being nothing at all? Or does this question not even make sense to ask?

4.3 Time – Is there a meaningful sense in which all times that have and will happen exist at once, or do some times only come into existence (as time passes)? Note that the theory of relativity seems to undermine the possibility of a single-speed of time that is the same for all observers.

4.4 Morality – Is there any form of morality that is “objectively” correct? For instance, can moral statements like “murder is always wrong” be true or false in the way that “I once purchased a fedora” is either true or false? If any sort of objective moral truth is possible, what then is objectively true about morality (e.g., utilitarianism, the categorical imperative, virtue ethics, theological ethics, etc.)?

4.5 Non-physical – does anything exist that is not merely made of atoms / not bound by our laws of physics, that can directly cause changes in our world (e.g. souls, ghosts, gods, spirits, the devil, etc.)?

4.6 Time travel – is time travel prevented by the laws of the universe? If it is not prevented by the laws of the universe, has it or will it ever happen? Potentially related: is it possible to exceed the speed of light, or is that literally impossible (as our current theories seem to tell us)?

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5. CONSCIOUSNESS

[Note that, by “consciousness,” I mean the state of having “internal experiences.” A being has consciousness if there is “something that it’s like” to be that being. For instance, there is something that it’s like to be you, but not something that it’s like to be a chair. You have internal experiences, like experiencing the taste of a pineapple or the color of a red apple, but a chair has no experiences. You have consciousness, in the way I’m using the term, but a chair (almost certainly) doesn’t.]

5.1 Justification – Why is there consciousness at all? Couldn’t the universe be just the same as it is now except without any internal experiences at all (i.e., with no consciousness)?

5.2 Requirements – What sort of configurations of matter are necessary to give rise to consciousness? Would it be possible to build a physical device to measure consciousness? If so, what would such a device need to be like?

5.3 Physics – How do we unify the existence of consciousness with the currently known laws of physics (since examining our known laws of physics would not allow you to infer that consciousness experiences even occur)?

5.4 Quantum – Does the human brain exploit quantum physics in a meaningful way, such that it is hard to understand what the brain is doing without using a quantum mechanical explanation?

5.5 Free Will – Why do we have the persistent sense of having free will, even though (given our current understanding of physics) our actions are fully and completely determined by whatever happened a moment before (plus quantum uncertainty)?

5.6 Minimal – Which beings have consciousness? Do atoms? Viruses? Bacteria? Blood cells? Lice? Ladybugs? Spiders? Snails? Frogs? Mice? Beavers? Toucans? What’s the “simplest” possible brain or system or algorithm that can experience consciousness?

5.7 Evolution – Did consciousness come about as a result of evolution (i.e., was it created by selection pressures), and if so, what is its survival function exactly?

5.8 Algorithmic – Is it possible for an algorithm run on a digital computer to experience consciousness?

5.9 Intelligence – Can something be much more intelligent than human beings (broadly speaking) and not have consciousness? Can something behave just like a human in all ways relevant to intelligence and yet not experience consciousness (i.e., can “philosophical zombies” exist?)

5.10 Teleportation – If a teleportation device existed that could make an essentially perfectly accurate copy of you out of new atoms, with all your memories and personality intact, but it destroyed your original self just before assembling the new copy of you, would the copy be you, in the same sense that you one second from now is still you?

5.11 Macro – Is it possible (even if extraordinary difficult) for a large-scale, purely mechanical system to have consciousness, for instance, a massive machine made out of gears and pulleys? Could a very large number of people, if they were all carrying out coordinated movements that were designed to match the algorithmic information processing of a brain, temporarily create a large-scale consciousness?

5.12 Agent – What’s the right definition to use for a single “being” or “agent” that properly distinguishes it from all other beings, while still handling even weird thought experiments. (For instance, where a person’s brain is split into two but continues to operate, or where a brain is slowly replaced with pieces of another brain over a long period of time, without ever ceasing operation)?

5.13 Finality – Does all experience cease after death, as atheists typically believe and as spiritual and religious people typically deny?

1 In the beginning, the big bang created the heavens.

1 In the beginning God created the heaven and the earth.

2 The universe was formless and infinitesimal. Plasma hotter than a thousand suns permeated the explosively expanding fabric of space.

2 And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.

3 Inflation slowed, the universe cooled, and there were protons and neutrons.

3 And God said, Let there be light: and there was light.

4 The particles were good; and were differentiated from anti-particles, becoming ever so slightly more abundant.

4 And God saw the light, that it was good: and God divided the light from the darkness.

5 The particles were called matter, and the anti-particles were called anti-matter, and there was the beginning and there was the ending of the first millisecond.

5 And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.

6 Temperatures plunged as space grew, and matter annihilated anti-matter. Nearly all particles were wiped from the universe, but quadrillions upon quadrillions of photons remained.

6 And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.

7 And there were neutrons that bonded with the protons.

7 And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so.

8 And there was ionized hydrogen and deuterium, with only a single proton for each. And there was the beginning and there was the ending of the first four minutes.

8 And God called the firmament Heaven. And the evening and the morning were the second day.

9 And the Universe cooled still more so that electrons could orbit protons, and the first stable atom was born.

9 And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so.

10 Photons dislocated from matter, propagating through space for all eternity, to be called the cosmic background radiation.

10 And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good.

11 And there were fluctuations in the uniformity of matter, with gravity seeding galaxies across a billion light years.

11 And God said, Let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the earth: and it was so.

12 Great clouds of gas condensed, and dark matter and dark energy were abundant, and it was good.

12 And the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.

13 There was the beginning and there was the ending, the first billion years.

13 And the evening and the morning were the third day.

14 And from gas and dust, great lights formed in the expanse of the heavens, called the stars, which mark the seasons.

14 And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:

15 And they gave their light upon many trillions of coalescing planets.

15 And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.

16 And there were moons that formed around the planets, and reflected the light of the suns.

16 And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.

17 And so too did the Earth form from the rotating dust cloud of the solar nebula, and the Sun gave it warmth.

17 And God set them in the firmament of the heaven to give light upon the earth,

18 And the Sun governed the day and the night, and it was good.

18 And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.

19 There was the beginning and there was the ending, the first nine billion years.

19 And the evening and the morning were the fourth day.

20 The molten Earth cooled and its crust hardened. An atmosphere formed and condensed, changing Earth into an ocean planet.

20 And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven.

21 And lifeless molecules swarmed in the water, colliding, breaking and re-forming in billions of configurations, and it was good.

21 And God created great whales, and every living creature that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and God saw that it was good.

22 And one of the molecules that formed was a replicator, configured to reshape other molecules in its own likeness. It was fruitful and multiplied itself, filling the waters in the seas.

22 And God blessed them, saying, Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth.

23 There was the beginning and there was the ending, ten billion years.

23 And the evening and the morning were the fifth day.

24 The replicators copied imperfectly, and most variants died off. But a few, able to copy even faster than their ancestors, proliferated.

24 And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind: and it was so.

25 Materials for replication were scarce and competition was fierce, and only the fittest varieties survived.

25 And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.

26 And through myriad minute changes over millions of generations, some evolved the power to destroy and others mechanisms for their defense.

26 And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.

27 And descendants that banded together were more likely to survive, and from these great colonies arose multicellular organisms.

27 So God created man in his own image, in the image of God created he him; male and female created he them.

28 The creatures multiplied and photosynthesized. They produced oxygen which transformed the air, and they spread onto the accreting continents.

28 And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.

29 And they became every plant and fish, every insect and reptile, every bird and mammal, forever fighting for the survival of their genes, the remnants of the original replicators.

29 And God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every tree, in the which is the fruit of a tree yielding seed; to you it shall be for meat.

30 And there was the platypus and opossum, the mole and wombat, the elephant shrew and elephant, the manatee and armadillo, the mole and bat, the camel and horse, the cat and rabbit, the rat and beaver, the squirrel and guinea pig, the colugos and lemur, the tarsier and gibbon, the orangutan and gorilla, the bonobo and chimpanzee, the homo habilis and homo erectus, the homo rhodesiensis and homo neanderthalensis, and then there was the human.

30 And to every beast of the earth, and to every fowl of the air, and to every thing that creepeth upon the earth, wherein there is life, I have given every green herb for meat: and it was so.

31 And humans considered themselves the center of all existence. And there was the end, and the beginning, 13.8 billion years.

31 And God saw every thing that he had made, and, behold, it was very good. And the evening and the morning were the sixth day.

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