 The first disagreement may not be very substantial. A CA-world is compatible, for instance, with an eternalist conception. The idea that the world’s next state is computed at any time step can be seen as a merely heuristic device, a “shortcut” for a more proper eternalist description in which the cell’s states are once and for all “stuck” in their space-time position (we did this ourselves when describing the first picture in this section as the complete space-time evolution of a micro-universe). 