Wow, great question! Let me try to brainstorm a bit about it - all improvised, I confess.
Indeed, the two situations seem to have some similarities. The Copenhagen interpretation of QM claims that observation collapses the wavefunction. The act of observation, hence, produces a new reality that would not be there, had no observation been made. In my essay, I claim that agents are also a creation of observers, and they would not be there, were there not an observer (endowed with a brain) producing it.
Can we make an even stronger analogy? When an observer identifies an agent, he or she does not change anything in the outer world, they only change the representation of the outer world that they carry in their brain: by defining the limits of the agent, they make a decision of what exactly they will represent as a separate concept, and what they will discard. Collapsing the wavefunction, however, seems to be a more dramatic action. It seems to imply a change in the outer world, banishing the possibility of interference between the branches of the wavefunction that prior to the collapse were evolving together.
Yet, within the Everett perspective, the collapse of the wavefunction loses the drama of the Copenhagen picture: All branches of the wavefunction continue to evolve, each one containing one version of the observer. So the collapse is no more than the view from inside-one-branch of an otherwise continuous process. The observer changes nothing of the outer picture, his or her experiments are just the result of perceiving a partial version of all what happens. But can we argue that evolving into one or other branch of the wavefunction is also a computation that brains cannot avoid performing, given the way they have evolved? Can we make the same claim as when observing purposeful agents?
In this respect, I believe the two systems are somewhat different. The sole interaction between the measuring apparatus and the quantum system under study collapses the wavefunction (or branches it, within the Everett picture), irrespective of whether there is a brain or not in play. Of course, a brain can only evolve in a system that receives information about the outer world, and is capable of representing that information. So by all means, brains must be endowed with measuring devices (our sensory systems, at the very least). So my conclusion would be:
- brains create agents when observing the world
- all measuring devices (not just brains) that interact with a quantum system collapse the wavefunction
- the sensory systems that a brain is fed with are examples of such devices.
There is much more to say, I guess, actually this is an excellent question! I'll post this right now, but will keep thinking about it, these ideas are just my first draft of an answer.
Is it not surprising that relativity, and QM, and thermodynamics all point out to an active role of the observer in what we so far had regarded as objective reality?
So hey, thanks a lot, this is truly fun!
ines.