Disagreement And Williamson On Evidence

For whatever reason, I was reading David Enoch’s draft of “Not Just A Truthometer: Taking Oneself Seriously (but not Too Seriously) in Cases of Peer Disagreement”, when I noticed something that surprised me:

Fifth, and again following the literature here, I will focus on cases where the disagreeing peers share all the relevant evidence, and indeed where this very fact is a matter of common knowledge between them. Typical examples include a simple arithmetical calculation (what evidence could anyone possibly lack here?), philosophical debates where all concerned know of all the relevant arguments, and perhaps also moral debates of a similar nature. 

This is probably pretty obvious, but the stipulation that the two parties to a dispute share all relevant evidence has very strange consequences for anyone who accepts Williamson’s thesis (E=K) that our evidence just consists of all and only those propositions that we know.

Two parties to a disagreement might share all relevant information prior to thinking about the issue, but once they begin thinking about the issue, they’ll make various inferences, and given that they end up disagreeing, they’ll probably infer different things.  If any of those things they inferred count as knowledge, then they no longer share the same evidence.

And so, with a casual stipulation at the beginning of their papers, Enoch and most other writers about disagreement have been brushing aside one of the more prominent theses in contemporary epistemology.

Postscript: I say “brushing aside” because this isn’t strictly an incompatibility.  You can maintain E=K, discuss the topic of disagreement with the stipulation of identical evidence, and then just admit that peer disagreement is not only a little bit uncommon, but incredibly unlikely.  This is not how the discussion proceeds, and there would be reason to carefully scrutinize any paper that did proceed that way.


Saint Patrick’s Day

I love Saint Patrick’s day.  Every year, conservatives dutifully stick to their principles and explain that Saint Patrick’s day is un-American because we don’t have hyphenated identities, and everyone just needs to assimilate.  It’s refreshing to note that they don’t just apply these ideas to people with darker skin.

The Mouse Is Not A Finger

I’m just now listening to it, and I still need to finish the last 15 minutes, but I’ll recommend episode 3 of Hypercritical, John Siracusa’s podcast with Dan Benjamin.

In the first half* of the podcast, John explains the vision behind the major UI changes planned for Mac OS X Lion, and really sold me on the vision.  Then in the second half, he explains that about half of it won’t work, and he’s probably right.

* The first portion is actually spillover discussion on backups from episode 2.  So it’s the first half of the main part of the episode.  That’s also a good episode.  Are you doing your backups properly?


No, this post isn’t about epistemology. Cosma Shalizi defends lottery players:

The benefit to playing the lottery comes entirely between buying the ticket, and when the winner is revealed. During this interval, someone who has bought the ticket can entertain the idea that they might win, and pleasantly imagine how much better their life could be with the money, what they would do with it, etc. It’s true that in some sense you always could thinking about “what if I had $280 million?”, but many people find it very hard to get our imaginations going on sheer will-power. A plausible and concrete path to the riches, no matter how low the probability, serves as a hook on which to suspend disbelief. In this regard, indeed, lottery tickets are arguably quite cost-effective. If a $1 lottery ticket licenses even one hour of imagining a different life, I don’t see how people who spend $12 for two or three hours of such imagining at a movie theater, or $25 for ten hours at a bookstore, are in any position to talk.

Despite having held this idea for years, I have never played the lottery, because I couldn’t begin to make myself believe.

This only applies for the largest lotteries. But in North Carolina, people drop a lot of money on smaller games that offer a better chance to win, but no more than a few hundred or a thousand dollars. Maybe the fantasy is still good enough to offset the monetary loss–so long as you’re thinking about the vacation you’ll take and not about having the money for your light bill.

Here’s my own bit of contrarianism: in those smaller lotteries, the expected value of winning may well be negative. On the plus side, there is the money and the enjoyment of winning. On the negative side, winning is positive reinforcement so you play more in the future. Thus, when my mother-in-law put $1 scratch off tickets in my stocking, I spent the next few minutes thinking “don’t win, don’t win”. Anyone who knows my history with video games will understand. Thankfully, while I won seven dollars, I have not been tempted to play in the meantime.

I actually told someone who was addicted to the lottery: “you don’t want to win–it’ll make you keep playing” and he responded “I guess that’s right.” So perhaps the theory is less contrarian than I think it is.

P.S The Slate article that Cosma links to is also a lot of fun.

The American Muslim Success Story

Every couple of weeks since it was published, something has made me wish that everyone in America would read Radley Balko’s article, The American Muslim Success Story. I forget the most recent provocation, but the article continues to be relevant. Everyone should read the article, and if you can twist the arm of one Palinite Republican into reading it, so much the better.

Obama Started Killing Americans, But I Mean…I Had Healthcare

The Obama administration has filed a brief arguing that no one can legally challenge their order for the assassination of Anwar al-Aulaqi because it would compromise “state secrets” (Washington Post, Glenn Greenwald). To review: Anwar al-Aulaqi is an American citizen living in Yemen. While he is suspected of aiding Al-Qaeda, he has never been convicted or even charged with a crime in the US courts. It is probable that he is guilty of crimes, and possible that he could be convicted, but Obama has pre-empted that by ordering his assassination, which can be carried out even if he is located outside of a combat-zone.

Claiming the power to assassinate Americans is odious enough, but the Obama administration has raised the stakes by claiming the courts cannot hear the case. Given the way the state secrets claim is made, does anyone imagine that the administration would ever allow a legal challenge to any assassination without crying about state secrets?

In effect, the administration is trying to lay the groundwork for a right to kill Americans that is not subject to real judicial oversight. So long as the legislature is cowed, the constraints on the President would be extremely weak. I suppose it’s nice to think that Obama isn’t the type to abuse this–though I hope you’re asking yourself what kind of man asserts this power–but does that change all that much? What matters are the powers themselves, not the man holding them.  Obama is not a tyrant, but he is repeatedly demanding tyrannical powers.  Not only may future Presidents be less trustworthy, the powers themselves are abhorrent.

I would not want to slander the majority of Democrats by saying that they’ll support this decision just because it’s Obama. That would be unfair, as most Democrats have the good sense to say that this kind of decision is really just awful, before pivoting and talking about healthcare. With this unpleasant business forgotten, they can get on to explaining how the “professional left” is full of people who “need to be drug tested”, see the glass as “half full”, and act petulant when the President doesn’t give us “world peace.”

There’s too many accomplices out there.

We’ll Enforce The Law, But We Don’t Know What It Is

This is an a noteworthy story about a man who refused to answer the Border patrol agents’ questions about the details of his overseas trip, and was held for 90 minutes as he spoke to various officials. His refusal to answer questions is perfectly legal–absent reason to arrest or otherwise interrogate him in relation to some crime, a US Citizen has an unconditional right to reenter the US. Note that he did make an adequate customs declaration, without false statements, and allowed them to perform all searches they asked to do.

There’s a lot of points that can be said, but one lesson fits with what we already know–an enormous number of law enforcement officers do not know what they need to about citizens’ rights. This is amply demonstrated every time a citizen or journalist is arrested for exercising their right to record the police.* While I vacillate on whether Lucaks’ action was worthwhile, that it pressures law-enforcement to learn about their legal responsibilities can only be a good thing. It is simply unacceptable for law-enforcement officers to be ignorant in this fashion.

* Just in case you want legal advice, there is a patchwork of local and state laws. In some places, many forms of recording may be illegal. But in a majority of places, it is legal and there are hundreds, if not-thousands of arrests for citizens exercising their rights to record police in jurisdictions that allow them to do so.