• ## YAAS Epistemology

Epistemology is the study of knowledge. Its central questions include “What is knowledge?” and “Is knowledge possible?”. This post tries to give an overview of the field highlighting key terminology, open problems, and categories of responses to those problems.

Epistemology is the study of knowledge.

### What is knowledge?

For literally millenia, people were content to think of knowledge as justified true belief (Plato 360BC). Let’s break that down briefly:

Belief
A belief is mental content held as true. Thinking to myself, with conviction, “I am a human.” and “I am a dragon.” are each equally examples of beliefs.
True
Alas, only one of the above claims is true. Even if I have very convincing hallucinations of breathing fire and flying, “I am a dragon” is merely justified belief. It’s not true and so not knowledge.
Justified
On the other hand, if I stumble onto true belief, it still doesn’t count as knowledge. If you roll a 100-sided die and hide the result under a cup, I don’t know that the result is 64 even if I believe it and it turns out to be true—I have no justification for the belief.

It’s only when beliefs are both true and justified that they count as knowledge. Sounds reasonable, right?

#### Gettier problem

Not to Edmund Gettier. In a three page paper (Gettier 1963), he presented two compelling counterexamples to this analysis. An example of this vein of anecdote is:

Whetu is driving home from work one day and happens to see her coworker Sigrún in a Vanagon. She thinks to herself, “Ah, one of my coworkers owns a Vanagon.” However, unbeknownst to Whetu, Sigrún does not actually own the Vanagon she was driving—she was in the midst of stealing it. But, coincidentally, one of Whetu’s other coworkers does own a Vanagon.

So Whetu’s initial belief—“One of my coworkers owns a Vanagon”—turns out to be true and justified (we’ll count seeing someone driving a car as convincing justification for believing that they own it). But intuitively, we’re reluctant to accept that Whetu knows that one of her coworkers owns a Vanagon. It seems like she just got lucky—her mistaken justification was rescued by a fact that she would be surprised to learn.

• ## Shilling for Anki

I like Anki.

### The decline and rise of long-term memory

I used to scorn long-term memory. My brain is an exquisite organ for vanquishing conundra, thank you very much, not some library card catalog. I assume I assimilated this attitude from discussion like1:

But, after reading up on pedagogy in articles like the one we discussed earlier, “[I] no longer see longterm memory as a repository of isolated, unrelated facts that are occasionally stored and retrieved; instead, it is the central structure of human cognitive architecture.” (Sweller 2008)

### Spaced repetition

Thus, I present my own entry in the burgeoning subgenre of spaced repetition software encomia.

Briefly, spaced repetition software optimally schedules flashcard review to radically boost retention of information in long-term memory. Anki is one such program. I’d heard of Anki in the past but only managed to acquire the habit of regular review more recently. I’ve performed a total of 14306 reviews of 3811 cards during review sessions and reviewed on 58 of the last 58 days (Let it never be said that I do things in half measures.). This is probably too intense and more than I’d recommend for most people. But that information should serve to calibrate you as to how much experience I have with Anki.

#### The feel of a thing

The dominant feeling I now have is a mild frustration at the betrayal of present me by past me—so much of my prior reading and general intellectual development was wasted effort. If we each had anterograde amnesia and forgot 100% of what we’d read or otherwise experienced, we’d surely take a different approach to life. We wouldn’t just wander along learning and forgetting in an endless cycle. But the truth of our memories is not so far off!

“The meteorite itself was so massive that it didn’t notice any atmosphere whatsoever,” said Rebolledo. “It was traveling 20 to 40 kilometers per second, 10 kilometers — probably 14 kilometers — wide, pushing the atmosphere and building such incredible pressure that the ocean in front of it just went away.”

These numbers are precise without usefully conveying the scale of the calamity. What they mean is that a rock larger than Mount Everest hit planet Earth traveling twenty times faster than a bullet. This is so fast that it would have traversed the distance from the cruising altitude of a 747 to the ground in 0.3 seconds. The asteroid itself was so large that, even at the moment of impact, the top of it might have still towered more than a mile above the cruising altitude of a 747. In its nearly instantaneous descent, it compressed the air below it so violently that it briefly became several times hotter than the surface of the sun.

“The pressure of the atmosphere in front of the asteroid started excavating the crater before it even got there,” Rebolledo said. “Them when the meteorite touched ground zero, it was totally intact. It was so massive that the atmosphere didn’t even make a scratch on it.”

Unlike the typical Hollywood CGI depictions of asteroid impacts, where an extraterrestrial charcoal briquette gently smolders across the sky, in the Yucatan it would have been a pleasant day one second and the world was already over by the next. As the asteroid collided with the earth, in the sky above it where there should have been air, the rock had punched a hole of outer space vacuum in the atmosphere. As the heavens rushed in to close this hole, enormous volumes of earth were expelled into orbit and beyond — all within a second or two of impact.

“So there’s probably little bits of dinosaur bone up on the moon,” I asked.

“Yeah, probably.”

Survival in the first hours of the Cenozoic

Life confined to Earth’s surface would have perished well before incineration. After ignition temperature was reached, fires would not have spread from one area to another in the usual way. Rather, fires would have ignited nearly simultaneously at places having available fuel.
The shortest-lived child of Prohibition actually survived to adulthood. This was the change in drinking patterns that depressed the level of consumption compared with the pre-Prohibition years. Straitened family finances during the Depression of course kept the annual per capita consumption rate low, hovering around 1.5 US gallons. The true results of Prohibition’s success in socializing Americans in temperate habits became apparent during World War II, when the federal government turned a more cordial face toward the liquor industry than it had during World War I, and they became even more evident during the prosperous years that followed.50 Although annual consumption rose, to about 2 gallons per capita in the 1950s and 2.4 gallons in the 1960s, it did not surpass the pre-Prohibition peak until the early 1970s.

In MUSE a distinction is made between present and past perfect (i.e., within the perfect aspect, tense is marked). Perfect means that the action is completed. AAVE has two additional markers for aspect which extend the perfect:

Muse AAVE
present perfect I have walked I have walked
completive n/a I done walked
remote time n/a I been walked
Study 1 (N = 228) examined 49 common variants (SNPs) within 10 candidate genes and identified a nominal association between a polymorphism (rs237889) of the oxytocin receptor gene (OXTR) and variation in deontological vs utilitarian moral judgment

• ## The moral imperative and mortal peril of maximizing

### The world as we understand it

A single death is a tragedy; a million deaths is a statistic. —Probably not Joseph Stalin

We humans are famously bad at finely-tuned and well-calibrated caring. In an early study on scope neglect, experimental subjects were willing to pay $80 to save 2,000 migrating birds from drowning in oil ponds and$78 to save 20,000 (Desvousges et al. 1992). Alas, our sentiments are not a precision instrument.

But suppose that our moods better mapped to the world as we understand it:

Whatever betrayal you feel watching Doubt, the betrayal would feel more than 300 times as sharp. 300 abusers represents just Pennsylvania. The full tally is unknown and probably unknowable.

Whatever loss you feel watching Up, you’d be struck by it again and again for each of the approximately 80,000 miscarriages per day across the world (Obstetricians, Gynecologists, and others 2002).

Whatever despondency you feel watching Winter’s Bone, your feelings would be magnified in depth and breadth by the knowledge that 836 million people in the world live on less than \$1.25/day (UN 2015).

Whatever precarity you feel watching Grapes of Wrath, you’d feel it a shattering 2 billion times more intensely for the approximately 25 percent of the world population that live on small farms.

Whatever despair you feel watching The Skeleton Twins, you would feel that way for each of the estimated 334 million people in the world with depression (Organization and others 2017).

Whatever loneliness you feel watching Three Colors: Blue, you might feel that same feeling 2,500 times a day for each of the one quarter of US women who are widowed by age 65 (Berardo 1992).

Whatever shame you feel watching Tokyo Sonata, you’d feel it 192 million times over for the global unemployed in 2018 (International Labour Organization 2018). Then you’d remember that any period of unemployment’s negative effects last at least 10 years [louis2002].

Whatever horror you feel watching The Battle of Algiers, you’d feel it just the same for each and every one of the approximately 80,000 people who will die from battle in state-based conflicts this year (Roser 2018).

Whatever impotence you feel watching Killer of Sheep, you’d remember that there are over 900,000 black people in Los Angeles alone living under flawed structures and institutions.

Whatever grief you feel watching Amour, you’d have around 3.5 minutes to recover before the grief of another US death by stroke crashed over you.

Whatever hopelessness you feel watching Cool Hand Luke, it would echo and rebound magnified from the cells of more than 10 million detainees (Walmsley and others 2015).

Whatever suffocation you feel watching Requiem for a Dream, you’d feel it on behalf of the approximately 164 million people with substance use disorders (Ritchie and Roser 2018).

Whatever ache you feel watching Grave of the Fireflies, it would hollow you out each day along with the approximately 815 million people who are chronically undernourished (Organization 2014).

But, for good or for ill, we are bounded and parochial. We cannot comprehend in any but the most abstracted ways the daily ruin that nature visits on us, that we visit on ourselves and each other.

### The world as we imagine it

[T]hose who would play this [utopian] game on the strength of their own private opinion … and would brave the frightful bloodshed and misery that would ensue if the attempt was resisted—must have a serene confidence in their own wisdom on the one hand and a recklessness of other people’s sufferings on the other, which Robespierre and St. Just […] scarcely came up to. (Mill 1879)

The tragedies of life on Earth are no recent revelation. The Epic of Gilgamesh—our earliest surviving great work of literature—is about the hero’s vain attempt to undo the great tragedy of his life.

For some, the knowledge that tragedy has been with us from the beginning inspires not acquiescence but determination that we might leave it behind before we reach the end. These are names that go down in history. Names like:

• ## A non-exhaustive list of putative problems with ignorant priors

The principle of indifference (a.k.a. the principle of insufficient reason) suggests that when considering a set of possibilities and there’s no known reason for granting special credence to one possibility, we ought to assign all possibilities the same credence (which, on the Bayesian point of view, is also a probability). For example, when someone asks what the result of a 6-sided die roll is, the principle of indifference recommends we assign a probability of 1/6 to each outcome. Slightly more interesting is that it also recommends assigning a probability of 1/6 to each outcome even when we’re told the die is weighted as long as we’re not told how it’s weighted.

There’s a definite intuitive plausibility and appeal to this rule. But it turns out there are a lot of difficulties when it comes to actually operationalizing it. Below, I list some of the problems that have been raised over the years. Some of these problems seem silly to me and will doubtless seem silly to you. Others strike me as important. I list them all here regardless and ignore any claimed solutions for the moment.

### Coarsening

“What is the origin country of this unknown traveler? France, Ireland or Great Britain?”

Naive application of the principle of indifference (NAPI) suggests we assign probability 1/3 to each possibility.

The question can be rephrased: “What is the origin country of this unknown traveler? France, or the British Isles?”.

In this case, NAPI suggests we ought to assign a probability of 1/2 to each possibility.

So, depending on the framing, we assign probability 1/2 or 1/3 to the same outcome—the traveler is from France.

Description Outcome Probability
France, Ireland, or Great Britain France 1/3
France or British Isles France 1/2

### Negation

“I’ve just pulled a colored ball from an urn containing an equal number of red, black and yellow balls. Which color is the ball? Red, black, or yellow?”

NAPI suggests we assign probability 1/3 to each possibility.

The question can be rephrased: “Which color is the ball? Red or not red?”.

In this case, NAPI suggests we ought to assign a probability 1/2 to each possibility.

So, depending on the framing, we assign probability 1/2 or 1/3 to the same outcome—the ball is red.

Description Outcome Probability
Red, black or yellow Red 1/3
Red or not red Red 1/2

“I have an equilateral triangle inscribed in a circle. I’ve also chosen a chord in the circle randomly. What is the probability that the chord is longer than a side of the triangle?”

If we construct our random chords by choosing two random points on the circumference of the circle and construct a chord between them, we find that the probability of a long chord is 1/3.

If we construct our random chords by choosing a random radius and then constructing a chord perpendicular to a random point on that radius, we find that the probability of a long chord is 1/2.

If we construct our random chords by choosing a random point inside the circle and constructing a chord with that point as its midpoint, we find that the probability of a long chord is 1/4.

So depending on our framing, we assign probability of 1/4, 1/3 or 1/2 to the same proposition.

Description Outcome Probability
Chord by two points on circumference Long chord 1/3
Chord by random radius and point Long chord 1/2
Chord by random point as midpoint Long chord 1/4

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