alt Hacker NewsWe know for a fact that for humans consciousness only exists in parts of the brain and can be turned off using drugs, sleep and accidents.
It is almost certainly the same for all animals with a brain.
Given the fact that plants have no brain it is a reasonable assumption they have no consciousness. It may be wrong, but given all evidence it is, so far, the best assumption.
We usually call assumptions based on our best current understanding scientific facts.
Alternative hypothesis: Given that plants do not have a central nervous system, it is reasonable to expect they have a distributed consciousness.
Recall that most plants avoid building single-purpose organs, as the odds that 70-80% of the plant gets eaten are high. Plants have evolved to survive massive loss of body parts.
I've read some studies on plant consciousness which shows that plant awareness can be turned off with anesthetics