So according to you when can you qualify something as capable of hearing
1. Vibrate according input to the sound, is that hearing?
2. Generate electrical signals according to the sound, is that hearing?
3. Amplify electrical signal, does we cross the hearing mark?
4. Record the signal to a cassete tape (or use an ADC -> mp3), are we hearing yet?
5. Play it back through a speaker. Sure, we should be hearing now!
At which point exactly would you say the thing is definitely hearing?