The experience machine
Robert Nozick, Anarchy, State, and Utopia (1974) · also Nozick’s experience machine, experience machine thought experiment, the pleasure machine
Neuroscientists can plug you into a machine that gives you any experiences you want, indistinguishable from real life. You could feel that you are writing a great novel, falling in love or climbing Everest, while in fact you float in a tank with electrodes in your brain. You would not know you were plugged in.
What it tests If all that mattered were how life feels from the inside, you should plug in for life. Would you, and if not, what else matters?
The case
Robert Nozick asks you to imagine a machine, run by superb neuropsychologists, that can give you any experience you desire. You can choose a life of writing a great novel, making a friend or reading an interesting book, and while plugged in you will think and feel that it is really happening. In fact you will be floating in a tank with electrodes attached to your brain. You can preprogram your whole life’s experiences, and you will not know you are in the machine. Should you plug in?
Nozick, writing in Anarchy, State, and Utopia (1974), thought most people would refuse, and that their refusal teaches something.
What it is meant to show
The target is hedonism about well-being: the view that the only thing that makes a life good for the person living it is its pleasant experiences. If hedonism were true, the machine would be the best deal on offer, since it can deliver more and better experiences than reality. If you would not plug in, something besides experience matters to you.
Nozick named three things. We want to do certain things, not merely have the experience of doing them. We want to be a certain kind of person, and a person in a tank is an indeterminate blob. And we want contact with a deeper reality, rather than a world limited to what people could construct.
The replies
Bias, not insight. Experimental philosophers have tested the intuition. Felipe De Brigard asked people to imagine that they were already in an experience machine and could leave it; many chose to stay. That suggests part of our reluctance to plug in is status quo bias, a preference for whatever life we currently have, rather than a discovery about value.
Fear of the machine. Some argue that people refuse because they worry the machine might fail, or doubt it could really be indistinguishable from life. These are not reasons the case allows, so they do not count against hedonism.
Biting the bullet. Some hedonists accept that the machine life is as good for the person as any other, and explain away the contrary intuition as attachment to things that are usually good as means to pleasant experience.
Why it matters now
When Nozick wrote, the machine was science fiction. Now there are partial versions. Immersive virtual worlds offer experiences of achievement and adventure, and AI companions offer the experience of being understood, admired or loved without another person who understands, admires or loves. The experience machine asks the right question of them: is the experience the whole of what we want from friendship and love, or do we want the relationship to be real? Related questions about what we owe one another, and what we can take from systems that only seem to be someone, are explored in Is an AI chatbot an informant or an instrument? The machine’s epistemic cousins are the brain in a vat and the simulation argument.
Terms
Questions people ask
What is the experience machine?
It is a thought experiment from Robert Nozick’s Anarchy, State, and Utopia (1974). A machine can give you any experiences you like, indistinguishable from real life, for the rest of your life. Nozick argued that most of us would not plug in, which shows that we care about more than how our lives feel from the inside.
What is the experience machine an argument against?
Hedonism about well-being, the view that only pleasant experiences make a life go well for the person living it. If that were true, a life in the machine would be at least as good as any real life. Nozick concluded that we also want to actually do things, to be a certain kind of person, and to be in contact with reality.
Would most people plug into the experience machine?
Most people say no when asked. Some experimental work, notably by Felipe De Brigard, suggests the reluctance may partly reflect status quo bias: when people are told they are already in a machine and asked whether to leave it, many choose to stay.
Is the experience machine relevant today?
Increasingly. Immersive virtual worlds, and AI companions that offer the experience of friendship or love without another person on the other side, are partial experience machines. Nozick’s question, whether experiences are all that matter, is now a practical one.
Sources and further reading
- Nozick, R. (1974). Anarchy, State, and Utopia. New York: Basic Books, 42–45.
- De Brigard, F. (2010). If you like it, does it matter if it’s real? Philosophical Psychology 23(1): 43–57.doi.org/10.1080/09515080903532290
- Hedonism, Andrew Mooreplato.stanford.edu/entries/hedonism/