"Teacher, why can observation affect the result? Sorry, teacher... Am I too stupid and not suitable for learning quantum physics?"
"Don’t worry. You are not stupid. Quantum theory can by no means be comprehended by ordinary people. Not that observation can impact the result, but both results exist at the same time. Only when you begin to observe it can you know what happened actually. Imagine Schrödinger's classic thought experiment, where a cat was kept in an absolutely sealed black box, in which a poisoned bottle, controlled by a radioactive switch, filled with highly toxic cyanide, was placed later. The rate of decay of the radioactive material was uncertain, and you never knew when the switch would be triggered, so before you opened the black box and observed it, you had to realize the cat may either be still alive or could be dead, right?"
"Well... I seem to have understood that, but teacher, why use a cat to do this experiment? Wasn’t it cruel?"
