Pleasure or Reality? The Experience Machine Debate

Conclusions often drawn from the famous thought experiment seem problematic.

Posted Mar 13, 2019

In his famous 1974 book Anarchy, State and Utopia, Robert Nozick presents his famous experience machine thought experiment. In this thought experiment, we are asked to imagine a scenario in which technology is so advanced that we can plug ourselves into a virtual reality machine for a very long time. When plugged in, we will experience life as very pleasant indeed. Before we plug in we can decide for ourselves what types of experiences we will have. Once the electrodes are connected to our head we will not know, of course, that we are plugged into the machine; we will believe that we really are receiving the Nobel Prize for Literature for writing the best novel of the century; that we really are extremely clever and attractive; that we really are painting like Picasso; or that we really are having a passionate love affair. (In fact, for all we know, we may be right now in an experience machine and not "really" reading this post from the screen in front of us.) We need not worry, in this thought experiment, about nutrition, safety or health; they are all taken care of. Nor are there any problems with family members that need care: We have no families, or they are fine, or they too will plug into the experience machine if we do. (I have slightly altered some of the details Nozick presents.)

Now the question arises: If there were such an opportunity for you, the reader, to plug in, would you? For life? For 20 years? For four years? Why would or wouldn't you?

Nozick believes that most people will choose not to plug into the machine. This may sound odd, since in the experience machine they are likely to experience life as far more pleasant than in real life. One way to interpret the refusal to plug into the machine is to suggest that people are not interested only, or mostly, in pleasure; it is not the only, or main, thing that people want in life. This may serve as an argument against what has come to be called hedonic theories of well-being, according to which people's well-being consists only of the balance of pleasure over pain. The refusal to plug into the machine suggests that we do not only want to feel subjective pleasure in our lives; we also want our lives to have some objective value. For example, we do not only want to be pleased by the thought that we wrote a good novel; we want to actually write a good novel. We want the achievement to be real, and we want to really be the ones making it.

The refusal to plug into the experience machine also has implications for discussions on meaning in life. Subjectivist theories of meaning in life hold that our sensation of meaningfulness or other subjective conditions is what makes life meaningful. Objectivist theories of meaning in life hold that attaining objective value in life is what makes life meaningful. Hybridist theories of meaning in life hold that both subjective and objective conditions have to be fulfilled in order that life be meaningful. The anticipated results of the experience machine thought experiment count against purely subjectivist views of meaning in life.

In his paper, "If You Like It, Does It Matter If It's Real?" Felipe de Brigard casts some doubt on both the anticipated results and on the way they are often interpreted. Brigard conducted experiments in which he presented to participants a somewhat different question than the one Nozick discussed: Brigard requested participants in the experiment to imagine that they already are connected to the experience machine, and then asked them whether they would like to disconnect. He presented three variations to the scenario: In the first, no information was given to participants about what they were in real life. In other words, participants were not told how real life would be for them if they unplugged from the machine. In the second variation, participants were told that in real life they were prisoners in a maximum security prison. In the third variation, participants were told that in real life they were multimillionaire artists living in Monaco.

Of those exposed to the first variation, only 54% said that they wanted to unplug. Thus, when told that they already are in the machine and that in order to live in reality they need to change the condition they are in, many did not prefer reality to the machine.

In the second variation, in which those unplugging would find themselves in a maximum security prison, only 13% preferred reality. This suggests that the pleasantness of life does, in fact, make a lot of difference to people thinking about the experience machine.

Somewhat surprisingly, in the third variation, in which moving to reality meant living the life of a multimillionaire artist in Monaco, 50% of the participants said that they would unplug. The difference between the second and third variations still shows that pleasantness of life does play an important role, but one would expect, if it played an important role, that the percentage of participants wishing to unplug would be higher in the third variation than in the first variation.

In his discussion, Brigard emphasizes what has come to be called in psychological research the status quo bias: People often show a preference to retain the conditions in which they find themselves rather than to change them; people like the status quo. For example, in an oft-mentioned experiment, Jack L. Knetsch gave rewards to two groups of undergraduate students. Each student in the first group got a mug bearing the university's logo, while each student in the second group got a chocolate bar. Then, all of the students were offered the option of trading the rewards they received with the students of the other group. But almost 90% of them preferred to keep the reward they had been given.

Brigard suggests that the many people's intuitive preference not to plug into the experience machine, in Nozick's version of the thought experiment, may well not have to do with the importance of retaining contact with reality or with the incorrectness of hedonism (or, it could be added, with the wrongness of subjectivism about meaning in life). It is likely, argues Brigard, that people's preference not to plug into the machine is mainly affected by the status quo bias. 

Nozick's experience machine thought experiment, then, may prove less than it is often taken to. And it calls for much more discussion and deliberation. But this also brings up another issue that Brigard emphasizes at the end of his paper: Nozick and many of the philosophers who wrote about his thought experiment did not check empirically whether indeed most people do not wish to plug into the machine. They just predicted that this would be the case, without actually checking it. This is problematic, since the argument and much of the discussion following it relied on claims about how most people would react to this thought experiment without relying on any empirical data about how most people in fact choose. Many of those who wrote about the issue seem to have merely extrapolated from their own preferences to humanity at large. Some others seem to have extrapolated from their own preferences and from those of a few of their close friends to humanity at large. And yet some others also asked their philosophy students about their preferences, not always heeding the reasons the students raised. But these are surely not representative or reliable samples. There seems to be much more empirical and philosophical work to do on the topic before we draw conclusions about hedonism, subjectivism, and the nature of well-being and of meaning in life.


Robert Nozick Anarchy, State and Utopia (New York: Basic Books, 1974), 42–45.

Felipe De Brigard, "If You Like It, Does It Matter If It’s Real?" Philosophical Psychology 23 (2010): 43–57.

Jack L. Knetsch, "The Endowment Effect and Evidence of Nonreversible Indifference Curves," American Economic Review 79 (1989): 1277–1284.