Brent meeker writes (quoting SP): > > Every physical system contains if-then statements. If the grooves on the > > record were different, > > then the sound coming out of the speakers would also be different. > > That's not a statement contained in the physical system; it's a statement > about other > similar physical systems that you consider possible. You could as well > say, (print > "Hello world.") contains an if-then because if the characters in the string > were > different the output would be different.
I don't see how you could make the distinction well-defined. Consider the following two programs: (a) input: x if x=1 print "hello" if x=0 print "goodbye" data: 1 and (b) print "hello" As written, program (a) will print "hello" just as consistently as program (b). It looks like program (a) has a conditional in that if the 4th line were "data: 0" it would print "goodbye". However, program (b) would also print "goodbye" if that string were substituted for "hello". Both programs do the same thing, and both would do something else if the programmer intervened and changed them. In (a) the code is separated into "program" and "data" but as you pointed out recently there is no real difference between these. Subroutines within a larger program could be intelligent entities interacting with a virtual environment with no input from outside the program in the same way as intelligent entities within the real universe interact with the environment with no input from outside the universe. It's worth standing back at this point and looking at what a computer + program + data really is: a collection of plastic, metal, and semiconductors assembled in a specified way which has no choice but to follow the laws of physics. The if-then statements amount to a particular physical configuration such that stimulus x will make the computer behave one way while stimulus y will make it behave in a different way. This is not fundamentally different to saying that, for example, a car is configured so that it will turn left or right depending on which way the steering wheel is turned. In both situations, dumb matter blindly follows the laws of physics. The difference is in the details, complexity and intended purpose of each device; it is not that the computer interacts with its environment and handles counterfactuals while the car does not. Stathis Papaioannou _________________________________________________________________ Be one of the first to try Windows Live Mail. http://ideas.live.com/programpage.aspx?versionId=5d21c51a-b161-4314-9b0e-4911fb2b2e6d --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to firstname.lastname@example.org To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list -~----------~----~----~----~------~----~------~--~---