Here is my attempt at providing an experimental protocol to determine whether an entity is conscious.

If you are just looking for the stuffed animal music video skip to 23:28.

Are you the only conscious being in existence? How could we actually test whether other beings have conscious minds?

Turing proposed to test the existence of other minds by measuring their verbal indistinguishability from humans (the famous “Turing Test” asks computers to pretend to be humans and checks if humans buy the impersonations). Others have suggested the solution is as easy as connecting your brain to the brain of the being you want to test.

But these approaches fail for a variety of reasons. Turing tests can be beaten by dream characters and mindmelds might merely work by giving you a “hardware upgrade”. There is no guarantee that the entity tested will be conscious on its own. As pointed out by Brian Tomasik and Eliezer Yudkowsky, even if the information content of your experience increases significantly by mindmelding with another entity, this could still be the result of the entity’s brain working as an exocortex: it is completely unconscious on its own yet capable of enhancing your consciousness.

In order to go beyond these limiting factors, I developed the concept of a “phenomenal puzzle”. These are problems that can only be solved by a conscious being in virtue of requiring inner qualia operations for their solution. For example, a phenomenal puzzle is to arrange qualia values of phenomenal color in a linear map where the metric is based on subjective Just Noticeable Differences.

To conduct the experiment you need:

1. A phenomenal bridge (e.g. a biological neural network that connects your brain to someone else’s brain so that both brains now instantiate a single consciousness).
2. A qualia calibrator (a device that allows you to cycle through many combinations of qualia values quickly so that you can compare the sensory-qualia mappings in both brains and generate a shared vocabulary for qualia values).
3. A phenomenal puzzle (as described above).
4. The right set and setting: the use of a proper protocol.

Here is an example protocol that works for 4) – though there may be other ones that work as well. Assume that you are person A and you are trying to test if B is conscious:

A) Person A learns about the phenomenal puzzle but is not given enough time to solve it.
B) Person A and B mindmeld using the phenomenal bridge, creating a new being AB.
C) AB tells the phenomenal puzzle to itself (by remembering it from A’s narrative).
D) A and B get disconnected and A is sedated (to prevent A from solving the puzzle).
E) B tries to solve the puzzle on its own (the use of computers not connected to the internet is allowed to facilitate self-experimentation).
F) When B claims to have solved it A and B reconnect into AB.
G) AB then tells the solution to itself so that the records of it in B’s narrative get shared with A’s brain memory.
H) Then A and B get disconnected again and if A is able to provide the answer to the phenomenal puzzle, then B must have been conscious!

To my knowledge, this is the only test of consciousness for which a positive result is impossible (or maybe just extremelly difficult?) to explain unless B is conscious.

Of course B could be conscious but not smart enough to solve the phenomenal puzzle. The test simply guarantees that there will be no false positives. Thus it is not a general test for qualia – but it is a start. At least we can now conceive of a way to know (in principle) whether some entities are conscious (even if we can’t tell that any arbitrary entity is). Still, a positive result would completely negate solipsism, which would undoubtedly be a great philosophical victory.