i have thought of something. how do we know anyone/thing else other than yourself exists?

arguments:

1)According to the brain in the vat argument, all your senses are 'hacked', so you will not be able to find out if all you sense are even real at all. Hence the only thing you can prove that exists is yourself.

2)In some cases, one has dreams so vivid that he cannot tell whether it is real or not. he can interact, sense, and think about things and people in the dream, and he can also move and change view-basically everything that one can do in the 'real life'. however, all these objects and characters do not even need to be the input of an external controller- it can be figments of one's imagination, just like in dreams.

hence I hypothesize that it is not possible to prove that anyone else except yourself exists. therefore i think that suicide bombers are kinda strange.(i'm being mild here.)

darn. the market for good mushiking cards is getting smaller. i'd better sell it for even a meagre profit before the fad is over.