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Life in the Plural: If There Were Two of You, Would “You” Exist?

According to philosopher Angus Menuge, there can’t be two of you, because two things cannot be one thing.

In the third podcast of the series, “Unity of Consciousness,” Walter Bradley Center director Robert J. Marks interviews Angus Menuge, professor and chair of philosophy at Concordia University, on unique features of human consciousness, including the fact that our experiences are a unity, which has prompted some interesting thought experiments, for example those of Richard Swinburne. But here’s another one: What if there really were two of you?

This portion begins at 06:49 min. A partial transcript, Show Notes, and Additional Resources follow.

Robert J. Marks: What is the idea of “too many thinkers” in philosophy?

Angus Menuge (pictured): The simple view of personal identity is that your soul or your mind is always you. That’s a dualist view.

The complex view is based on some kind of continuity, either continuity of brain states, physical continuity, or continuity of memories, mental states.

The scenarios described create problems for this view. Here are a few examples: Suppose that there is an ontological three-dimensional copier. It can duplicate people physically. So then you and your doppelganger — which is just like you in every way, physically — share a common origin. This copy was made from you and there’s continuity. Since the continuity is there, it would seem that there’s now two of you. The problem is there can’t be two of you, because two things cannot be one thing.

Note: “Human organisms have brute-physical persistence conditions. If your brain were transplanted, the one who ended up with that organ would be uniquely psychologically continuous with you (and this continuity would be continuously physically realized). On any psychological-continuity view, she would be you: the person would go with her transplanted brain. But no organism would go with its transplanted brain. The operation would simply move an organ from one organism to another. So it seems, anyway. It follows that if you were an organism, you would stay behind with an empty head. Even though this is never going to happen, it shows that according to psychological-continuity views we have a property that no organism has, namely possibly moving from one organism to another by brain transplant.” – “The Too-Many-Thinkers Problem,” Stanford Encyclopedia of Philosophy

The closest humans come to anything like “two you’s” is the case of inseparably conjoined twins who jointly control some body parts but separately control others but remain separate people:

“There is also a set of conjoined twins who have separate brains but a single body and share control of the body. The neurology of these twins is not fully understood, but there seems to be an implicit cooperation in movements and thoughts. My sense is that it is analogous to the ordinary cooperation of unconnected people in everyday life. We cooperate and do things together all the time — we collaborate on projects, carry heavy things together, etc. Conjoined twins do so more spontaneously and intimately. It’s strange but not completely unlike ordinary social life.” – Michael Egnor, “Are human brain transplants even possible? Mind Matters News

Bottom line: Human consciousness, all the more so its uncommon manifestations, is the most remarkable thing in our universe.

Next: Why don’t changes to our bodies create a different consciousness?

Here are the earlier portions of this discussion:

Part 1: Mystery: Our brains divide up events but we experience them whole That’s one of the conundrums of consciousness. Philosopher Angus Menuge notes that something that is not just our brains unifies our experiences from the partial information scattered across many neurons.

Part 2: How split-brain surgery underlines the unity of consciousness. At one time, some thought that if the brain were split, consciousness would be too, but that did not turn out to be true. Philosopher Angus Menuge thinks that “split personality” doesn’t mean two consciousnesses but loss of access to the information that integrates mental states.

Part 3: Why do we stay the same person over time? Why not split up? It would be a total fluke if all the different clouds of atoms that produce your brain would always produce the same consciousness. But they do. Philosopher Angus Menuge argues that you have one soul, at and over time. And that explains why, despite changes, you are one consciousness, at and over time.

Show Notes

  • 00:30 | Introducing Dr. Angus Menuge
  • 01:04 | Unity of consciousness
  • 03:04 | Split-brain operations
  • 04:55 | Split personalities
  • 06:49 | Too many thinkers problem
  • 11:06 | Why don’t bodily changes generate a different consciousness?
  • 14:28 | Elon Musk’s Neuralink

Additional Resources

Podcast Transcript Download

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Life in the Plural: If There Were Two of You, Would “You” Exist?