Closing remarks

Yeah, I finally watched Barack Obama’s half-hour message, online. It’s an excellent wrap-up to a too-long campaign and it hit all the right notes for me, anyway. Some of it is production values, of course, but there were genuinely affecting passages, especially when Obama tied his own story to the particular issues he addressed, as with education or health care. Folks have compared him to John F. Kennedy quite a bit, but I think actually the better parallel is with Abraham Lincoln – a man who essentially came from nowhere by dint of study, ambition, and genuine vision. He’ll have a lot to live up to if he wins – but I’ll be proud to punch my ballot for Barack Obama.

Postscript: What if, instead of public financing, we just gave every candidate a half-hour block of TV time to use as he or she would in the week before Election Day? This long form emphasizes, if anything, the sheer volume of substantive policy proposals that make up Obama’s platform – and might point up a candidate who didn’t have anything substantive to say.

Why do butterflies have four wings?

ResearchBlogging.orgIn this week’s PNAS is a tidy result that demonstrates what you ca get away with when you study invertebrates: butterflies and moths can still fly if their hindwings are amputated, but they can’t take evasive action [$-a]. That summary tells you just about all you need to about the reported experimental result; but the rest of the article has some interesting speculation.

Photo by me.

The authors, Jantzen and Eisner, start from the premise that the large, showy wings of butterflies should (very generally) make them major targets of predation. They note, however, that butterflies are also marked by highly erratic flight – an extreme maneuverability that makes it difficult for a predator to guess where a butterfly is going to be in the future based on its current trajectory. Maybe showy wings actually act as a kind of inverse protective coloration:

A bird, we suggest, could learn or inherently know that brightly colored airborne prey, discernible from afar, is not worth the chase. Too elusive to catch and, because of their [wing] scales, too slippery to hold … Birds might simply write butterflies off, and … relegate them all to the category of the undesirable, treating them as they treat noxious insects that they disregard.

Jantzen and Eisner’s experiment, in which they amputated butterflies’ hindwings, confirms that butterflies can still fly without the second pair of wings, but fly less erratically. Does the result confirm the authors’ major hypothesis, though? I’m not so sure. There are plenty of other reasons to have big, showy wings – mate attraction, or as placement for eye spots to fool predators – and plenty of butterflies and moths are comparatively small and non-showy. Jantzen and Eisner’s hypothesis smells more than a bit like adaptive story-telling, though it provides some food for thought.


B. Jantzen, T. Eisner (2008). Hindwings are unnecessary for flight but essential for execution of normal evasive flight in Lepidoptera PNAS, 105 (43), 16636-40 DOI: 10.1073/pnas.0807223105

Things you might not know about Bruce Schneier

Looks like security-centric ubergeek Bruce Schneier would give Chuck Norris a run for his money:

  • There are no prime numbers, just numbers Bruce Schneier hasn’t bothered to factor yet.
  • Bruce Schneier shaves with Occam’s razor.
  • When he was three, Bruce Schneier built an Enigma machine out of Legos.
  • When Bruce Schneier observes a quantum particle, it remains in the same state until he has finished observing it.

Some of these are too geeky for me, and I’ve read Cryptonomicon. To which Schneier contributed, natch.


Everybody uses Wikipedia these days. I go to the site at least once daily to find everything from the formula for great circle distance to the difference between gram-negative and gram-positive bacteria. Simson Garfinkel says Wiki-memory informs more than my half-arsed TA lectures and frantic data-crunching.

Wikipedia’s standards of inclusion–what’s in and what’s not–affect the work of journalists, who routinely read Wikipedia articles and then repeat the wikiclaims as “background” without bothering to cite them. These standards affect students, whose research on many topics starts (and often ends) with Wikipedia. And since I used Wikipedia to research large parts of this article, these standards are affecting you, dear reader, at this very moment.

And, he argues, that’s a very scary thing. Because Wikitruth is not the same as factual truth:

What makes a fact or statement fit for inclusion is that it appeared in some other publication–ideally, one that is in English and is available free online. “The threshold for inclusion in Wikipedia is verifiability, not truth,” states Wikipedia’s official policy on the subject.

This is a huge problem in light of the fact that many of the top peer-reviewed journals still haven’t gone open-source – you can usually link to an online abstract these days, but the text of articles is behind a subscription wall. And so a lot of science might as well not exist, as far as Wikitruth is concerned.

Yet the need to define truth in terms of third-party publications arises directly from Wikipedia’s crowdsourced model – authors are unverifiable, so the facts have to be based in something other than personal expertise. Google tried to get around this with the personality-driven Knol, but that’s not exactly taken off.

Via Andrew Sullivan.

Towards an empirical morality

ResearchBlogging.orgAndrew Sullivan links to a thought-provoking 1998 essay by E.O. Wilson, in which the champion of sociobiology delves into the question of whether morality arises from divine revelation or natural selection. Wilson takes an interesting position, attempting to turn the question around by ninety degrees:

But the split is not, as popularly supposed, between religious believers and secularists. It is between transcendentalists, who think that moral guidelines exist outside the human mind, and empiricists, who think them contrivances of the mind. In simplest terms, the options are as follows: I believe in the independence of moral values, whether from God or not, and I believe that moral values come from human beings alone, whether or not God exists. [Italics sic.]

Photo by lumierefl.

Although this perspective pulls back from the God-vs.-Science dilemma, it doesn’t quite eliminate it. Science tends to lean towards the “moral values come from human beings alone” position, and not just because any “transcendent” source of morality is probably beyond the scope of scientific inquiry. Exhibit A is the “trolley dilemma” dissected eloquently in a 2006 episode of Radio Lab: To prevent a runaway trolley from hitting a group of bystanders, most people judge it moral to pull a lever to divert the trolley onto a side track, even if doing so kills one person standing on the side track. But ask them to push that single person into the path of the trolley to stop it hitting the crowd, and most people balk.

In the experiment at the focus of that Radio Lab episode, Joshua Greene and his coauthors used functional magnetic resonance imaging to look at brain activity in people considering the two variants of the trolley dilemma, and found evidence that the dilemma creates a conflict between rational and emotional responses [PDF]. “Rational” parts of the brain were active in the decision to pull the lever, but “emotional” ones were involved in unwillingness to push a person into the trolley’s path. As Greene et al. write:

The thought of pushing someone to his death is, we propose, more emotionally salient than the thought of hitting a switch that will cause a trolley to produced similar consequences, and it is this emotional response that accounts for people’s tendency to treat these cases differently.

This result suggests that there isn’t some universal, transcendent standard of morality by which people are making decisions – in either pushing or lever-pulling, the choice is whether or not to sacrifice one life for the sake of many. But something in the fundamental architecture of the human brain determines that sometimes morality is judged in purely utilitarian terms and sometimes it isn’t. This is the kind of data that bears on the transcendence versus empiricism debate that Wilson outlines.

But empirical morality seems to run directly into the “naturalistic fallacy,” conflating that which is with that which ought to be. Wilson argues that empirical morality does not assume that the innate moral judgments of the human brain are also the judgments we ought to make – instead, it requires constant introspection and re-examination of the consequences produced by society’s moral code:

The empiricist view recognizes that the strength of commitment can wane as a result of new knowledge and experience, with the result that certain rules may be desacralized, old laws rescinded, and formerly prohibited behavior set free. It also recognizes that for the same reason new moral codes may need to be devised, with the potential of being made sacred in time.

That seems an inherently progressive point of view, one not far removed from the way Jesus described a morality that built on and universalized the old Jewish law, as with revenge: “You have heard that it was said, ‘Eye for eye, and tooth for tooth.’ But I tell you, Do not resist an evil person. If someone strikes you on the right cheek, turn to him the other also.” (Matt. 5:38-9, italics mine) And Jesus also tells his disciples to judge prophets not by their appeal to some special (transcendent?) revelation, but “by their fruit,” the consequences of their teachings (Matt. 7:15-22).

Yet – how do we judge what is a good outcome and what is a bad one? Science is good for predicting the consequences of actions and moral positions, but it is unable to determine which ones are good. Ultimately, empirical morality must proceed from some basic ethical framework, some agreed-upon prior definitions of “good” and “bad.” But that’s not really a victory for the transcendentalists. Even a perfectly articulated Platonic morality needs data from which to proceed – how many people are in the trolley’s way, and how much mass it would take to stop the trolley. Morality without reference to the empirical world is worse than meaningless. And the only access we have to the empirical world and its mechanisms is the scientific method.


J.D. Greene, R.B. Sommerville, L.E. Nystrom, J.M. Darley, J.D. Cohen (2001). An fMRI Investigation of Emotional Engagement in Moral Judgment Science, 293 (5537), 2105-8 DOI: 10.1126/science.1062872

Powell endorses Obama, defends Muslims

Former Secretary of State Colin Powell officially endorsed Barack Obama for President on Meet the Press this morning. But, incredibly, that’s not the most important thing he had to say in the interview. Referring to the Republican whisper campaign that claims Obama is a crypto-Muslim, Powell said (around 4:38 in this video):

Well, the correct answer is, he is not a Muslim, he’s a Christian. He’s always been a Christian. But the really right answer is, “What if he is?” Is there something wrong with being a Muslim in this country? The answer is no, that’s not America. Is there something wrong with some seven-year-old Muslim American kid believing that he or she could be President? Yet I have heard senior members of my own party drop this suggestion, “He’s a Muslim, and he might be associated with terrorism.” This is not the way we should be doing it in America.

Powell puts his finger on the ugly nature of the Muslim Obama rumors, which has bothered me basically from the first time I heard it, but hasn’t been much discussed in any major media outlet: why should it make a difference if Barack Obama is Muslim? As long as he’s an American citizen, his religion shouldn’t matter in a run for the Presidency. On the Media only picked it up last week – though once they did, they dissect the issue with the acumen you’d expect. More even then the endorsement, which is a big deal, I hope Powell’s MTP appearance starts a conversation about this.