We spend our lives in several realms. The first is the ordinary physical world of objects that exist in space and time. Objects obey simple laws. When any object moves or changes, we can usually account for it in terms of other objects pushing it, or else of gravity or wind. We also live in a social realm of persons, families, and companies; those entities appear to be ruled by quite different kinds of causes and laws. Whenever a person moves or changes, we look for signs of intentions, ambitions, infatuations, promises, threats, and the like — none of which could affect a brick. We also live in a psychological realm — inhabited by entities we call by names like meanings, ideas, and memories. These, too, appear to obey different rules.
The causes in the physical realm seem terribly different from those that work in the social and psychological realms — so different that they seem to belong to different worlds In some respects our bodies act exactly like ordinary objects: they have shapes we can see and touch, and they have locations that change when we're dropped or pushed. Yet in other ways, our bodies act quite differently from other things, and this appears to be because of minds. But what on earth are minds? For ages people have wondered about the relationship between the mind and body; some philosophers became so desperate as to suggest that only the mental world is real and the real world is merely an illusion. (That idea just makes the problem worse, because it can't even explain why there seems to be a physical world.) Most thinkers have ended up with images that portray two different kinds of worlds, one of matter and one of mind, somehow connected by mysterious threads of spiritual causality, somewhat like the films and tendrils formed when sticky stuff is pulled apart. Certain modern physicists have even speculated that these connections are somehow involved with the uncertainty principle in physics, perhaps because that problem also confounds their usual conceptions of causality. I see no merit in such ideas because as far as I'm concerned, the so-called problem of body and mind does not hold any mystery:
Minds are simply what brains do.
Whenever we speak about a mind, we're speaking of the processes that carry our brains from state to state. And this is what makes minds appear to us so separate from their physical embodiments: it is because concerns about minds are really concerns with relationships between states — and this has virtually nothing to do with the natures of the states themselves. This is why we can understand how a society of agents like Builder will work without knowing the physical constitution of its agents: what happens depends only on how each agent changes its state in response to its previous state and those of the other agents that connect to it. Other than that, it does not matter in the least what are the individual agents' colors, sizes, shapes, or any other properties that we could sense. So naturally minds seem detached from physical existence. It doesn't matter what agents are; it only matters what they do — and what they are connected to.