In addition to being an excellent economist and writer, Dan Ariely has among the best syllable-to-letter ratios for any last name I’ve heard. I only learned how to pronounce AR-EE-el-EE on Feb. 27, when he visited Seattle to discuss Predictably Irrational. He warmed the crowd with a visual illusion I fell for; this YouTube clip is a variation. Carefully count the number of one- versus two-handed passes in the video.

If you haven’t watched the clip, don’t read on. If you have, the question isn’t about passes: did you notice the guy with the cell phone walk up to the door behind the girls with the ball? Ariely’s video was more obvious: men in black and white shirts passed two basketballs and a guy in a gorilla suit walked through. Like most of the rest of the crowd, I didn’t notice the gorilla because I was busy counting passes (18 in all, though it depends on whether one counts a pass at the very end). To judge from the self-conscious laughter when Ariely pointed this out to us and the few hands that went up when he asked how many of us saw the gorilla, many others were in my situation. And with that, we were primed with a metaphor for the brain’s ability to create mental illusions.

Ariely gave many examples of such illusions and preferences. For example, opt-in versus opt-out retirement systems have widely varying degrees of participation, as do countries with organ donations, depending on whether people are enrolled by default or must opt-in. It turns out that we seem to have difficulty with multiple, complex choices and a tendency to fall back on defaults in the face of these choices. I’m reminded of Philip Zimbardo’s The Lucifer Effect: Understanding How Good People Turn Evil, which shows how otherwise normal people who receive arbitrary authority and limited oversight can do evil acts. That tendency might be an aspect of a default option: obeying perceived authority.

Both Zimbardo and, implicitly, Ariely, argue that by becoming aware of such tendencies we can better correct or fight them. The tendency towards defaults, initial choices, and authority might also explain why change in societal attitudes often happens slowly: it takes generations for tides to shift and first decisions to be made anew. Paul Graham says, “I suspect there is some speed limit to the evolution of an economy. Economies are made out of people, and attitudes can only change a certain amount per generation.” Ariely’s research supports that conclusion, but I can also see how and why change might be accelerating: as people become more accustomed to change as the norm and as the first choice, it becomes more natural for the individuals who make up societies to reorient themselves faster to new choices. This could also help explain some of the findings in Gregory Clark’s A Farewell to Alms, which argues that the Industrial Revolution took off more because of attitudes and culture in England than other conditions. England’s culture during the Industrial Revolution had finally reached a place where change and innovation became the norm, and where society could support that change rather than relying on defaults like superstition or religion to explain worldly phenomena. It’s an intriguing hypothesis, though off the top of my head I can’t immediately think of a clever way to test whether change becoming a default norm might help change in the future, perhaps explaining why I’m not a behavioral economics professor.

Ariely also showed how we’re constantly using imperfect and imprecise knowledge to make decisions, allowing first decisions their power to frame how we think about something. In an experiment, Ariely read poetry to students and then asked how much groups of students would either pay or agreed to be paid to hear him recite poetry again shortly. The group asked how much they would pay offered to pay to hear Ariely read, and the group that he offered to pay demanded money. It would appear that the way he framed the question caused them to offer or demand money—and offer more or demand more the longer the reading went on. I would also note that, although Ariely gave an excellent econ talk, I’m not sure I would go for his rendition of “Leaves of Grass.” But students who asked how much they would pay did offer money for it because of the way Ariely framed the question.

Now that I know, I wouldn’t pay to hear him read poetry regardless of whether he asked. But if he’s in town for economics, I’d see him, and so should you. You’ll laugh and learn, and the former might be the optimal way to induce the latter.