Our Modular Selves: Science and the Philosophy of Self

One of the most enduring themes in western thought is the idea of The Self. Who am “I” and what does it mean “to be,” many philosophers have asked over the centuries. Thought provoking questions indeed, but most discussions of The Self make the mistake of assuming that it is something. The reality is that many modules that are constantly in conflict influence human beings. As prominent evolutionary psychologist Robert Kurzban explains, “the very constitution of the human mind makes us massively inconsistent.” We think that there is an “I” behind all of our cognition – a ghost in the machine – but this is largely a delusion.

Take our moral intuitions. Sometimes we are morally sound. In one experiment, researchers found that deliberately dropped envelopes were stamped and mailed one fifth of the time by complete strangers. Psychologist Jenifer Kunz found that when people receive a Christmas card from a family they do not know, they usually send one back in return. And in the famous Ultimatum experiment in which people are given $20 and the choice to either take all of it, split it $18/$2, or split it $10/$10, most split it evenly. Moreover, moral psychologists are demonstrating that babies as young as five to six months old have a “moral sense” towards people and objects outside of their kin.

On the other hand, consider Douglas Kenrick’s infamous study, which asked participants how often they thought about killing other people. Partnering with Virgil Sheets, Kenrick polled 760 Arizona State University students and found that “the majority of those smiling, well-adjusted, all-American students were willing to admit to having had homicidal fantasies. In fact 76 percent of the men reported such fantasies… [and] 62 percent of the so-called gentler sex had also contemplated murder at least once.” Furthermore, as Kenrick explains, “when David Buss and Josh Duntley later surveyed a sample of students at the University of Texas, they found similarly high percentages of men (79 percent) and women (58) percent admitting to homicidal fantasies.”

These findings aren’t surprising. Devil-angel, heaven-hell, and good cop-bad cop dichotomies have illustrated our inner conflicts for centuries. But isn’t it strange that these divisions occur inside of something we consider singular and unified? Of course, we are far from being singular or unified. As Jonathan Haidt says, “we assume that there is one person in each body, but in some ways we are each more like a committee whose members have been thrown together working at cross purposes” This should also seem obvious. Just think about weighing the short-term with the long-term: Should I eat Pizza now or go for a run? Should I keep drinking or go home to avoid the hangover? Should I continue working this job even though I don’t like it? Should I stay in this relationship even though it isn’t what it once was? To borrow an example from Kurzban, think of a few verbs to complete the sentence, I really like to ______ but afterwards I wish I hadn’t, and compare them to verbs that could complete the sentence, I don’t like to _______ but afterwards I’m glad I did. The first set of verbs sharply contrasts with the second set with the former illustrating the “impatient modules” and the latter the “patient modules.”

Why the inconsistencies? Put simply, we speak to ourselves, not ourself, and these inner dialogues depend on context and current states. For example, would you pay 30 dollars for a slice of pizza? Probably not. But what if you were starving on the African savannah and you happened to have 30 dollars? Or, to put it in more relatable terms, what if you were on one of those long-haul flights across the Pacific when after not eating for hours the person next to you pulls out a delicious slice of warm pizza and starts eating it. Suddenly, 30 dollars doesn’t seem so bad. Context and circumstance matter, duh. But what’s important is that the more specific our understanding of ourselves gets, the less general we can be in our explanations.

For example, let’s say you asked me if I liked coffee or beer. It depends. If it’s 9am I would say coffee and if it’s 9pm I would say beer. However, if I was cramming for a final exam, a 9pm coffee would sound very appealing. But let’s say I just got a bout of food poisoning and anything I put in my stomach was coming right back up. Now, both sound horrible. Ok, let’s say it’s Friday at 9pm and I don’t have to study for a test and I don’t have food poisoning but I am eating dinner with my girlfriend’s family and they look down upon alcohol. I would avoid beer like the plague. So I like beer as long as it’s 9pm, I don’t have a final exam to study for, I don’t have food poisoning and I’m not eating dinner with my girlfriend’s anti-alcohol family. I admit, I’m exaggerating. But there is an important point in drawing out these hypotheticals. And it is that, “the more we specify the context… the less we can generalize… [but] the less we specify… the more likely we are to miss something about how [we] decide.” This is one dilemma of economic theory in a nutshell: we say that humans are rational to understand how we decide as consumers but we know that this isn’t entirely true. However, we don’t sacrifice the entire theory just because it doesn’t apply universally.

Back to The Self.

The Scottish philosopher David Hume once again got it right long before the science by realizing Kurzban’s and Haidt’s points exactly. Hume held that The Self was more like a commonwealth, which upheld an identity not through some sort of essence or soul, as Plato would have said, but through different yet related elements. As Hume explained, “we are never intimately conscious of anything but a particular perception; man is a bundle or collection of different perceptions which succeed one another with an inconceivable rapidity and are in perpetual flux and movement.”  This is not to deny the importance of the self. As Daniel Dennett argues, the idea of the self, though delusional, acts as a convenient fiction. We tell ourselves stories to make sense of the world and our place in it; many times this is a good thing even though it is scientifically wishy-washy. But let’s at least keep in mind that The Self isn’t actually a thing the next time we think about our identities from the armchair.

Güth, W., Schmittberger, R., & Schwarze, B. (1982). An experimental analysis of ultimatum bargaining Journal of Economic Behavior & Organization, 3 (4), 367-388 DOI: 10.1016/0167-2681(82)90011-7

Kunz J (2000). Social class difference in response to Christmas cards. Perceptual and motor skills, 90 (2), 573-6 PMID: 10833755
Kenrick, D., & Sheets, V. (1993). Homicidal fantasies Ethology and Sociobiology, 14 (4), 231-246 DOI: 10.1016/0162-3095(93)90019-E