I have previously written (here) of my skepticism about the idea of replicating conscious human minds in computers. My skepticism remains intact, but setting that aside for the moment, I find the ideas presented by Michael Graziano in a 2013 article in Aeon Magazine to be fascinating.

Graziano’s piece, titled Endless Fun, begins by declaring “The question is not whether we can upload our brains onto a computer, but what will become of us when we do.”

Graziano recites some of the technical obstacles to mind uploading and proposes various ways it might be accomplished. Others have covered this ground before. But Graziano mentions something I’d not considered before: that a conscious digital mind could live in a digitally simulated environment, in which pretty much anything is possible:

That second version of you could live in a simulated world and hardly know the difference. You could walk around a simulated city street, feel a cool breeze, eat at a café, talk to other simulated people, play games, watch movies, enjoy yourself. Pain and disease would be programmed out of existence. If you’re still interested in the world outside your simulated playground, you could Skype yourself into board meetings or family Christmas dinners.

And then:

There are the issues that will arise if people deliberately run multiple copies of themselves at the same time, one in the real world and others in simulations. The nature of individuality, and individual responsibility, becomes rather fuzzy when you can literally meet yourself coming the other way. What, for instance, is the social expectation for married couples in a simulated afterlife? Do you stay together? Do some versions of you stay together and other versions separate?

So much for the self. What about the world? Will the simulated environment necessarily mimic physical reality? That seems the obvious way to start out, after all. Create a city. Create a blue sky, a pavement, the smell of food. Sooner or later, though, people will realise that a simulation can offer experiences that would be impossible in the real world.

To give just one disorientating example, it might include any number of dimensions in space and time. The real world looks to us to have three spatial dimensions and one temporal one, but, as mathematicians and physicists know, more are possible. It’s already possible to programme a video game in which players move through a maze of four spatial dimensions. It turns out that, with a little practice, you can gain a fair degree of intuition for the four-dimensional regime. To a simulated mind in a simulated world, the confines of physical reality would become irrelevant. If you don’t have a body any longer, why pretend?

But even this is relatively minor compared to what Graziano imagines next:

If simulated minds can be run in a simulated world, then the most transformative change, the deepest shift in human experience, would be the loss of individuality itself — the integration of knowledge into a single intelligence, smarter and more capable than anything that could exist in the natural world.

You wake up in a simulated welcome hall in some type of simulated body with standard-issue simulated clothes. What do you do? Maybe you take a walk and look around. Maybe you try the food. Maybe you play some tennis. Maybe go watch a movie. But sooner or later, most people will want to reach for a cell phone. Send a tweet from paradise. Text a friend. Get on Facebook. Connect through social media. But here is the quirk of uploaded minds: the rules of social media are transformed.

In the real world, two people can share experiences and thoughts. But lacking a USB port in our heads, we can’t directly merge our minds. In a simulated world, that barrier falls. A simple app, and two people will be able to join thoughts directly with each other. Why not? It’s a logical extension. We humans are hyper-social. We love to network. We already live in a half-virtual world of minds linked to minds. In an artificial afterlife, given a few centuries and few tweaks to the technology, what is to stop people from merging into überpeople who are combinations of wisdom, experience, and memory beyond anything possible in biology? Two minds, three minds, 10, pretty soon everyone is linked mind-to-mind. The concept of separate identity is lost. The need for simulated bodies walking in a simulated world is lost. The need for simulated food and simulated landscapes and simulated voices disappears. Instead, a single platform of thought, knowledge, and constant realisation emerges. What starts out as an artificial way to preserve minds after death gradually takes on an emphasis of its own. Real life, our life, shrinks in importance until it becomes a kind of larval phase. Whatever quirky experiences you might have had during your biological existence, they would be valuable only if they can be added to the longer-lived and much more sophisticated machine.

Graziano writes, “I am not talking about utopia. To me, this prospect is three parts intriguing and seven parts horrifying.”

To me, it might be one part horrifying and seven parts intriguing. I guess I’m assuming that even in this scenario it would be possible to pull back from the mind merge into your own individual identity at will. In any case, I’m not going to spend a lot of time worrying about it. I’m still doubtful that even the first steps down this road are possible.

It’s sure entertaining to think about, though.