If a tree falls in a forest and no one is around to hear it, does it make a sound?
If a tree falls in a forest and no one is around to hear it, does it make a sound? This riddle appears often in pop culture, and raises philosophical questions regarding perception, observation, and our knowledge of reality.
Most people, as well as scientists, assume that the observer doesn't change the tree-fall (although this is a difficult claim to prove -see Observer effect). Therefore, an unobserved tree-fall involves a "sound" as it is mechanically understood, but no sound experience. (see qualia)
This riddle illustrates John Locke's famous distinction between Primary quality and Secondary quality.
- Can we assume the unobserved world functions the same as the observed world? - eg.if I close my eyes is it still there? and does observation effect outcome?
- What is the difference between what something is, and how it appears? - eg. sound is the variation of pressure that propagates through matter as a wave
- Can something exist without being percieved? - eg.Sound is only sound if a person hears it