Conway’s Game of Life is Turing complete. So if computationalism about mind is true, we can have conscious life in the Game of Life.
Now, consider a world C (for Conway) with three discrete spatial dimensions, x, y and z, and one temporal dimension, t, discrete or not. Space is thus a three-dimensional regular grid. In addition to various “ordinary” particles that occupy the three spatial dimensions and have effects forwards along the temporal dimension, C also has two special particle types, E and F.
The causal powers of the E and F particles have effects simultaneous with their causes, and follow a spatialized version of the rules of the Game of Life. Say that a particle at coordinates (x0,y0,z0) has as its “neighbors” particles at the eight grid points with the same z coordinate z0 and surrounding (x0,y0,z0). Then posit these causal powers of an E (for “empty”) or F (for “full”) particle located at (x0,y0,z0):
If it’s an F particle and has less two or three F neighbors, it instantaneously causes an F particle at (x0,y0,z0+1).
If it’s an E particle and has exactly three F neighbors, it instantaneously causes an F particle at (x0,y0,z0+1).
Otherwise, it instantaneously causes an E particle at (x0,y0,z0+1).
Furthermore, suppose that along the temporal axis, the E and F particles are evanescent: if they appear at some time, they exist only at that time, perishing right after.
In other words, once some E and F particles occur somewhere in space, they instantly propagate more E and/or F particles to infinity along the z-axis, all of which particles then perish by the next moment of time.
Given the Turing completeness of the Game of Life and a computational theory of mind, the E and F particles can compute whatever is needed for a conscious life. We have, after all, a computational isomorphism between an appropriately arranged E and F particle system in C and any digital computer system in our world.
But because the particles are evanescent, that conscious life—with all its subjective temporal structure—will happen all at once according to the objective time of its world!
If this is right, then on a computational theory of mind, we can have an internal temporally structured conscious life with a time sequence that has nothing to do with objective time.
One can easily get out of this consequence by stipulating that mind-constituting computations must be arranged in an objective temporal direction. But I don’t think a computationalist should add this ad hoc posit. It is better, I think, simply to embrace the conclusion that internal subjective time need not have anything to do with external time.
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