Epilogue: Conclusion

Before leaving Poul Anderson's "Epilogue" (Explorations, New York, 1981), let us consider something that I should have mentioned before, Earth as seen from space by the returning Traveler crew:

no polar caps;
new continents, black and ochre instead of green or brown;
sea level temperatures from 80 to 200 Fahrenheit;
no atmospheric oxygen;
a cloudy atmosphere of nitrogen and its oxides, ammonia, hydrogen sulfide, sulfur dioxide, carbon dioxide and steam;
no chlorophyll or other complex organics;
metallic ground cover;
"This was no longer Earth." (p. 191)

This alone would not have been enough to tell us that a machine ecology has evolved but the description of Earth is in section II. Section I had already presented a robotic viewpoint character.

How plausible is what I call the "mechology"? The mineral-gathering sea rafts were already self-propelling and self-propagating and their templates were changed by the radiation of a nuclear war. Consequently, some changes were going to occur but surely their direction would have been unprecedented rather than an exact parallel of the now defunct biological evolution? It is plausible that some mechanisms would specialize in reproduction but far less plausible that they would develop sexual reproduction.

How plausible is consciousness? Mere computation is insufficient. Years ago, the philosopher John Searle remarked that a computer can be constructed from anything, for example from beer cans. However, beer cans are not the sort of things that can be conscious. A quantitative increase in the number of interactions between beer cans cannot lead to the qualitative change from unconsciousness to consciousness. What is needed is sensitive interaction with an environment leading to a central nervous system with at least an equivalent of neuronic interactions.

Mere computation is unconscious whereas neurons, as we know, generate consciousness. Thus, contra Asimov, a brain is more or other than a computer; a conscious robot is not just a mobile computer - and indeed Asimov's robots are described as possessing artificial brains. So the question is whether a robotic "brain" can duplicate, not merely simulate, animal or human brain functions. (I do not think that an immaterial soul is necessary.)

The robots think that the weak invasive "units" (human beings) were constructed by "persons" like themselves but how do they account for their own evolution from inanimate matter? If they were able to trace their evolution back to the sea rafts, then they would still have confronted a mystery.