If a tree falls in the forest and there is no one to hear it, it does not make a sound. This makes sense because sound is a perception. Without a perceiver, the falling tree just creates sound waves that are never perceived as sound. But, Schrödinger's cat applies to a living thing whose existence is not dependent on any outside observation. Why is it that the the cat cannot be said to be alive or dead until an observation is made? Seems that the status of the cat is simply unknown until an obervation is made. Please explain.