I wrote:
> Unless you know of some specific technical limitation, material shortage, > law of nature, or some other factor that will prevent progress toward > a given goal, it is safest to assume that progress will continue and the > goal will be met. There is no indication that robots are inherently unable > to do any phase of construction. > This is quite different from saying that "computers will definitely become sentient" (that is, self-aware; conscious). We do not yet understand what sentience is so we cannot predict with confidence that machines can achieve it. I expect they can. That is an unsupported opinion. I do not think biological carbon based computers (brains) have any special properties that cannot be emulated in silicon or other materials, but I could be wrong. Robot can already do complex assembly jobs better than the best-trained human being. They do these jobs in factories or on the operating table during Lasik eye surgery. They cannot work on construction sites outdoors mainly because these sites are chaotic and primitive, unlike organized factory environments. I expect that robots are used in the construction of prefabricated houses in Japan, and in things like prefabricated all-in-one bathtub and shower units in the U.S. They certainly could be. Perhaps it is not economical yet. In the future I expect every phase of house and building construction will be prefabricated. Only the final assembly will be on site. The site will be better organized than today, and construction will occur in a tightly organized and scheduled sequence, like the construction of a tall building in a major city today. When I say you can predict a technological outcome with confidence, I mean an outcome that has a clear path where the physics are understood. Also I mean something with a reasonably short-term payback, and a market that anyone can see exists. Thus, I would not predict that gigantic passenger interstellar space craft that operate close to the speed of light are inevitable. That is much too far from today's technology. On the other hand, I see no reason why interplanetary human colonization cannot be achieved, with travel time between the planets of weeks or months. This is especially likely if something like a space elevator can be constructed. It seems likely to me that an elevator is possible, based on the book "The Space Elevator." It is impossible to predict whether people will summon the will to make a space elevator, or the capital. I am sure that people will make robots capable of construction as soon as they can. Robot R&D is paying for itself at every stage, nowadays. The final R&D expense to make construction site robots will be tiny compared to the payback. Whether this will happen in 30 years, 50 years, or 100 years I cannot guess. I suppose it will happen in stages, starting with something like a robot that only lays roof shingles and hammers them down. I do not know enough about robots to predict this in detail. I am in the same position as someone looking at the steamship "The Great Western" in 1838 and predicting that someday, within 50 to 100 years, all transatlantic passenger service would be by steamship. That was a safe bet. As it happens, that took about 60 years. - Jed