>This sounds like metaphysical gobble-de-goop to me, along the lines of "If a tree falls in the forest and no one is around to hear it, is there any >sound?" Well of course there's sound,...
When a tree falls it displaces air,when humans are around they perceive this displacing of air as sound in their ears.
It all comes down on how we perceive and filter incoming signals in our brain.
It's all an illusion as some would say...