Dr. Nick Bostrom is a philosopher at Oxford university with interests in Anthropic Principle and the possibility that we are living in a computer simulation.
Nick Bostrom writes
"Many works of science fiction as well as some forecasts by serious technologists and futurologists predict that enormous amounts of computing power will be available in the future. Let us suppose for a moment that these predictions are correct. One thing that later generations might do with their super-powerful computers is run detailed simulations of their forebears or of people like their forebears. Because their computers would be so powerful, they could run a great many such simulations. Suppose that these simulated people are conscious. Then it could be the case that the vast majority of minds like ours do not belong to the original race but rather to people simulated by the advanced descendants of an original race. It is then possible to argue that, if this were the case, we would be rational to think that we are likely among the simulated minds rather than among the original biological ones. Therefore, if we don't think that we are currently living in a computer simulation, we are not entitled to believe that we will have descendants who will run lots of such simulations of their forebears. That is the basic idea. The rest of this paper will spell it out more carefully."
He concludes "that at least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a posthuman stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation."
Dr. Bostrom also points out: "If we start running simulations, that would be very strong evidence against (1) and (2). That would leave us with only (3)."
Dr. Bostrom directs his attention to future generations that run simulations on non-biological computers. The entities that are simulated are encouraged to believe that they have real biological brains. Such simulated people would believe that they have one type of brain (a biological one) when in fact they have only a simulated brain which is the product of some kind of electronic supercomputer.
I will assume that Dr. Bostrom's reasoning is correct. I will not attempt to verify his reasoning but only to thresh out minor points regarding the nature of the simulating and simulated minds.
Details of the arguement that can be removed while still allowing the arguement to stand
It is pertinent to note first of all that the technology being used to simulate is not an issue. The computers possessed by future generations may be made of silicon, or they may be organic. The advances of genetic engineering may well enable future generations to make biological computers. The technology being used would have no bearing upon the issue discussed by Dr. Bostrom's paper.
If the future generations are using biological computing technology then, it would not be a case of an electronic computer simulating minds that believe they have biological brains, but rather a biological computer (or brain) simulating people that believe that they have biological brains. The biological vs. silicon distinction is not one that that we need to stress.
And as Dr. Bostrom points out brains are not essential different from computers. Thus it does not effect Dr. Bostrom's arguement whether we call the hardware possessed by the future or forebear generations, "computers" or "brains."
As part of the proof of the likelihood that we are simulated brains, Dr. Bostrom requires that the future generations are capable of simulating a great number of their non simulated forebears. Dr. Bostrom seems to envisage future super computers running a great deal of simulations. However, in this age of the personal computer, it is not unreasonable to assume that the future generations use one piece of hardward for each simulated mind. The only stipulation is that they should be capable of making a very large number of such simulations.
It is also of note that intent is not particularly an issue either. Dr. Bostrom talks of future generations evolving to the stage where they are capable of "running" simulations, and this would suggest that they the simulations are created deliberately. There is nothing in the reasoning that asserts that the brains need to have been created deliberately.
It does not seem to be an issue whether the future generations have themselves become extinct or not. If the future generations have become extinct then this increases the likelihood that we are simulated rather than real.
While Dr. Bostrom hypothesises a situation in which a future race simulates their forebears using supercomputers, combining the last two points above it does not seem to affect the arguement if the simulation is being carried out by computers, possibly organic ones.
Those parts of the arguement that are essential
Having removed some of what I hope are non-essential parts of Dr. Bostrom's hypothesis, it is necessary to recap and clarify the types of situations that might be occuring.
Dr. Bostrom argues that whatever the situations there are minds and brains. Calling on the principle of "substrate independence," he argues that minds are run on hardware irrespective of the hardware type. This being the case, it is not clear whether minds are by their nature "simulated" entities, and whether this impacts on their existance. I will leave this question aside and merely point out that there are always mind-brain paris.
As a point of departure we may point to the following types mind-brain situations that we might find ourselves to be in.
1) Real forebears with minds and brains.
2) Simulated forebears with minds and simulated brains.
3) Real subquent generation simulating brains (computers) that are runing programs to simulating those in situation 2.
4) Real subsequent generations with minds and brains, that possess and control computers as described in (3).
As previously noted, it is does not necessary that the simulating computer-brains have masters,(4) so I will ignore them from the following discussion. Additionally on closer examination, the mind-brain situations (2) and (3) above are identical. So the question as to whether we are simulated becomes.
(1') Are we minds of real brain hardware
(2') Are we minds of simulated brains being run on simulating machines
Dr. Bostrom uses the pertinent analogy of the "java virtual machine". Java is a computer language that runs on a virtual, or simulated computer. The question as to whether we are simulated or not is rather similar to asking whether we are java programs or assembly language programs, the latter being programs that run on real machines. ]
He also asserts, as noted above that if we start running simulations, that would be very strong evidence that we are simulations. He is thinking of electronic simulations. At the present time our electronic simulation technology is not such that they are very convincing, yet. They are slowly getting that way, and it is partly the ability of computers to create convincing simulations that has lead to the increase in speculation that simuation may occur in the future, and that it may be already occuring now.
However, while our computer simulation technology is certainly advancing, we are aware that biological simulation technology is more advanced. We are aware that we dream and that our dreams are sometimes convincing simulations. Hence we are aware that a highly evolved simulation technology already exists.
Thus, if Dr. Bolstrom's reasoning is correct we should assume that we are the simulated brains running on virtual machines within biological computers.
Hence, Dr. Nick Bolstrom, and I, are very likely to be simulations and we should behave accordingly.
Posted by timtak at March 29, 2004 01:55 AM