(June 20, 2011 at 11:42 am)Rev. Rye Wrote: There are only three types of statements that can be totally disproved to absolute certainty: If you can prove that one statement is true, then any statement that is in direct contradiction to that proved statement is disproven. Ex: If it can be proven that if I am in my home in the Chicago suburbs, at any given time, then any statement that I am in, for instance, Ethiopia at the same time is automatically disproven. The other type of statement that can be disproven is if there is a logical contradiction in the statement. Ex: There are square circles on the cereal box. Since a square is a four-sided polygon, and a circle doesn't have sides to speak of, there is a logical contradiction in the statement and it is disproven. The third type of statement, however, is more relevant to the argument at hand. If one is searching for something, and it can be absolutely proven that the thing is not there, then it can be disproven. Needless to say, the smaller the area to be searched, and the larger the thing to be found, the easier it is to disprove a statement. Ex: If you go to an open field and do not see a live tyrannosaurus Rex in that field, you have disproven that there is a live T-Rex there.I have a few nit-pickings with your examples here:
1) I wouldn't use time-based location as a good example for the first type of statement. For one, you can say both "I was in London at 6AM" and "I was in England at 6AM" and both statements could be equally true, but secondly, the bizarre nature of quantum mechanics means that some things can exist in two locations at the same time. A better example of a contradiction would be a simple one, for instance: "I am not a man" is a direct contradiction to "I am a man".
2) A circle has one side.
3) I think you'd have to go further in order to say that the T-Rex was "absolutely proven" not to be in the field. The T-Rex could be, for instance, behind you, or invisible, or camouflaged, etc. There is the famous example by Carl Sagan of the dragon in the garage which illustrates this point.
