Regarding the age old conundrum of the tree falling in the forest. According to Barclay, there is no sound if there is no mind to hear it. I am thinking that there may be no human around hence no human auditory organs to absorb the waves and send the message of "sound" to the brain.....but that is a bit anthropocentric. The forest is full of creatures that have auditory organs, so some brains will hear the sound....some minds will perceive the sound of a crashing tree, no? (listening to Nigel Warburton's A Little History of Philisophy)

I agree. I don't know what Berkeley says about whether any nonhuman animals possess minds, but on his view, I take it, nonhuman animals would need to possess minds in order to perceive anything. Indeed, according to Berkeley, not only does the tree make no sound unless a mind perceives the sound, but the tree doesn't even exist without a mind to perceive it. (Even if no finite mind perceives the tree, Berkeley attributes the tree's existence to the tree's being perceived by God's mind.)

Notice, too, that if we construe "a sound" dispositionally, i.e., as simply a disturbance that would be heard if there were a normally equipped listener to hear it, then sounds can occur even with no listeners (human or nonhuman) on the scene.

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