[hackernewds]

I think you're misplacing the reasoning for the pain argument as "they can't feel pain the same way mammals do" whereas the contending logical argument is actually "we should avoid eating plants for the same reason we should animals - that is, it would be against their desires". The plant reflex is an indication of the latter.

Else you could easily ethically qualify meat eating that is limited to the consumption animals killed while blinded and under the influence of anaesthetics.

[nefitty]

I see what you mean. I took it for granted that it's clear that sentience is a prerequisite to the capability of having desires. If someone did argue that plants have desires then I would question what they mean: either they're implying conscious preference of future states, desire predicated on sentience or they mean some metaphysical teleological conception of desire. The first two are mistakes, the last is not really the type of argument that I find fascinating beyond its relevance to social ritual or linguistic games.