I'd try a different tack to get there
Stylistically, I would organize the article around the cleverness of the experiments. I'd invite the reader to pause and think of how to test the questions at hand, with hints. This has the benefits of stretching people's minds, making people less prone to arguments from ignorance because it confronts them with the fact they couldn't think of how to test something and thought it impossible, making them feel good when they can think of how to test it, and it might even lead to someone thinking of a novel and superior way to do so.
Then I'd linger on how details of the experiment disambiguates subjects' reasons behind actions. This makes the issue an exercise in problem solving rather than receiving a teacher's password from authority.
It is of course lukeprog's show, and he's doing a great job. His way has its advantages.
Related: Fake Selfishness, Not for the Sake of Pleasure Alone, Not for the Sake of Happiness (Alone), Value is Fragile, Fake Fake Utility Functions
- Mohammed Ibn Al-Jahm Al-Barmaki
In a 1990 experiment, Jack Dovidio made subjects feel empathy for a young woman by asking subjects to imagine what she felt as she faced a particular problem.1 Half the subjects focused on one problem faced by the woman, while the other half focused on a different problem she faced. When given the opportunity to help the woman, subjects in the high empathy condition were more likely to help than subjects in the low empathy condition, and the increase was specific to the problem that had been used to evoke empathy.
What does this study say about altruism and selfishness?
Some people think that humans are purely selfish, that we act for selfish motives alone. They will re-interpret any counter-example you give ("But wouldn't you sacrifice your life to save the rest of the human species?") as being compatible with purely selfish motives.
Are they right? Do we act for selfish motives alone?
Let's examine the evidence.2
We begin with a rough sketch of human motivation. We have 'ultimate' desires: things we desire for their own sake. We also have 'instrumental' desires: things we desire because we belief they will satisfy our ultimate desires.
I instrumentally desire to go to the kitchen because I ultimately desire to eat a brownie and I believe brownies are in the kitchen. But if I come to believe brownies are in the dining room and not the kitchen, I will instrumentally desire to walk to the dining room instead, to fulfill my ultimate desire to eat a brownie. Or perhaps my desire to eat a brownie is also an instrumental desire, and my ultimate desire is to taste something sweet, and I instrumentally desire to eat a brownie because I believe that eating a brownie will satisfy my desire to taste something sweet.
Of course, desires compete with each other. Perhaps I have an ultimate desire to taste something sweet, and thus I instrumentally desire to eat a brownie. But I also have an ultimate desire for regular sex, and I believe that eating a brownie will contribute to obesity that will lessen the chances of satisfying my desire for regular sex. In this case, the 'stronger' desire will determine my action.
The full picture is more complicated than this,3 but we only need a basic picture to assess the claim that we only act for selfish motives alone.
We might categorize ultimate desires like this:4
Psychological egoists think all ultimate desires are of type 2. Psychological hedonists are a subset of egoists who think that all ultimate desires are of type 1. Psychological altruists think that at least some ultimate desires are of type 4. If some ultimate desires are of type 3, but none are of type 4, then both egoism and altruism are false.
Previously, I presented neurobiological evidence that psychological hedonism is false. In short: desire and pleasure are encoded separately by the brain, and we sometimes desire things that are not aimed at producing pleasure, and in fact we sometimes desire things that do not produce pleasure when we get them.
But can we also disprove the claim that we act for selfish reasons alone (psychological egoism), by showing that normal humans have desires for the well-being of others?
The standard theory of altruism in psychology is the empathy-altruism hypothesis, which says that altruism exists in humans and is often the result of an empathic emotional response to another's distress.5 Experiments have uncovered a plausible causal chain from perspective-taking to empathy to the motivation of helping behavior, and shown that this chain is probably incompatible with psychological egoism.
Of course, showing that empathy causes helping behavior does not win the day for altruism over egoism. The egoist may say that, for example, empathy causes sadness and that people are motivated to help because they believe helping is the best way to alleviate their own sadness. Or perhaps people believe that helping people in some circumstances will make them feel good, or that failing to help will make them feel bad, and this is what motivates them to help.
Daniel Batson and other researchers have spent several decades running experiments that allow the empathy-altruism hypothesis to be compared to specific versions of the egoism. We can't review all those studies here,6 but let's examine a few of them.
Testing the Aversive-Arousal Reduction Hypothesis
One egoistic hypothesis explains helping behavior by saying that the sight of someone in distress causes an aversive reaction, and this (and not empathy) causes a desire to relieve the aversive emotion by helping the person in distress.
The Dovidio experiment described above undermines the naive version of aversive-arousal reduction hypothesis, but the egoist may insist that one's distress is increased when one feels empathy, and that the increased helping that follows empathy is due to increased distress. In contrast, the altruist maintains that empathy evokes an ultimate desire to help, which leads to helping behavior.
How can we test these competing hypotheses?
Batson says that in the condition with high-empathy where escape is easy (condition 3), the aversive-arousal reduction hypothesis predicts a low level of helping behavior, while the empathy-altruism hypothesis predicts a high level of helping behavior.
Batson conducted 6 experiments to test these predictions. All 6 experiments confirmed the empathy-altruism hypothesis over the aversive-arousal reduction hypothesis. Let's consider one of them.8
In one experiment
The results confirmed the empathy-altruism hypothesis over the aversive-arousal reduction hypothesis:10
Testing the Empathy-Specific Reward Hypothesis
Another egoistic hypothesis claims that helping behavior is motivated by the expectation of a reward. But this doesn't explain Dovidio's results - that empathy increases helping behavior. Still, the egoist might maintain that helping behavior is especially rewarding when one feels empathy for the distressed person. Call this the empathy-specific reward hypothesis.
This version of egoism predicts the helper will not be rewarded (by a jolt of pride, or whatever) if she is unable to relieve the target's distress, either because there's nothing she can do or because someone else helps the target before she can.
The empathy-altruism hypothesis says that people are motivated by an ultimate desire that the target's distress be alleviated. The empathy-specific reward hypothesis (a version of egoism) predicts that the helper will not be rewarded if she is unable to personally relieve the target's distress.
To test between the two hypotheses, Batson told11 participants that
Again, the results confirmed the empathy-altruism hypothesis over the empathy-specific reward hypothesis.
Conclusion
In these and many other experiments, the empathy-altruism hypothesis has been confirmed over a wide variety of naive and sophisticated versions of egoism.
Batson concludes:
Thus, it seems we probably do not act for the sake of selfishness alone.
Notes
1 This technique for inducing empathy in subjects had previous been tested by Stotland (1969) and others.
2 This article draws heavily from the more detailed review of the evidence available in Stich et al. (2010). That article also reviews evolutionary hypotheses about altruism, which the authors find (as yet) unpersuasive. Also see Eisenberg & Miller (1987); Dovidio et al. (2006).
3 For a fuller discussion of concepts of desire and human motivation, see Schroeder (2004). For a more recent explanation of how human motivation works, see Glimcher (2010).
4 Image from Stich et al. (2010).
5 By 'empathy', I mean something like Batson's (1991: 86) stipulated definition in terms of "feeling sympathetic, compassionate, warm, softhearted, tender, and the like." By 'distress' I mean something like Batson's (1991: 117) stipulated definition in terms of "self-oriented feelings such as upset, alarm, anxiety, and distress."
6 But, see Batson (2011); Batson et al. (1991, 1998).
7 Stich et al. (2010), pp. 177-179.
8 Batson et al. (1981), experiment 1.
9 Stich et al. (2010), pp. 180-181.
10 Image from Stich et al. (2010), p. 181.
11 Batson et al. (1988), experiment 1.
12 Stich et al. (2010), p. 198.
13 Batson et al. (1991), p. 174.
References
Batson (2011). Altruism in Humans. Oxford University Press.
Batson, Batson, Slingsby, Harrell, Peekna, & Todd (1991). Empathic joy and the empathy–altruism hypothesis. Journal of Personality and Social Psychology, 61: 413–426.
Batson (1998). Altruism and prosocial behavior. In Gilbert & Fiske (eds.), The Handbook of Social Psychology, Vol. 2 (pp. 282-316). McGraw-Hill.
Batson, Duncan, Ackerman, Buckley, & Birch (1981). Is empathic emotion a source of altruistic motivation? Journal of Personality and Social Psychology, 40: 290–302.
Batson, Dyck, Brandt, Batson, Powell, McMaster, & Griffitt (1988). Five studies testing two new egoistic alternatives to the empathy–altrusim hypothesis. Journal of Personality and Social Psychology, 55: 52–77.
Dovidio, Allen, & Schroeder (1990). The specificity of empathy-induced helping: Evidence for altruistic motivation. Journal of Personality and Social Psychology, 59: 249–260.
Dovidio, Piliavin, Schroeder, & Penner (2006). The Social Psychology of Prosocial Behavior. Lawrence Erlbaum Associates.
Eisenberg & Miller (1987). Empathy and prosocial behavior. Psychological Bulletin, 101: 91–119.
Glimcher (2010). Foundations of Neuroeconomic Analysis. Oxford University Press.
Schroeder (2004). Three Faces of Desire. Oxford University Press.
Stich, Doris, & Roedder (2010). Altruism. In Doris (ed.), The Moral Psychology Handbook (pp. 147-205). Oxford University Press.
Stotland (1969). Exploratory studies of empathy. In Berkowitz (ed.), Advances in Experimental Social Psychology, Vol. 4 (pp. 271–313). Academic Press.