Don't plants move their leaves to follow the sun?
Yes. This indicates that plants have the ability to react to an
outside stimulus. However, a simple response to an outside
stimulus does not, in and of itself, indicate the ability to feel
pain. As an example, an electric doorbell can also respond to an
outside stimulus. It detects the pressure of a human finger, and
it responds by ringing. However, the fact that the doorbell can
react this way to the presence of your finger does not imply that
the doorbell is conscious. Similarly, the ability of plants to
move their leaves to follow the sun does not, in and of itself,
indicate consciousness.
Follow up questions:
How do you know that plants can not feel pain?
What would you do if we hypothetically discovered that plants do indeed feel pain?
Aren't there some religions which believe that plants possess a soul?
What if we killed the animals without inflicting any pain on them?
How do you know that other animals can feel pain?
Where in the animal kingdom does consciousness begin?
Is it ok to kill animals which do not possess consciousness?