to me, i think it's more like awareness than intention.
unintented is like unknowing.
sometimes, if people are originally ignorance/unaware, they might
be guided by the other people, peers and surrounding media, and
hence their intention are as if okay to them. eat only mah. people
are all doing it. right or not, they wouldn't know.
unknowingly eat already, next life come back, cycle happen
again.
there's still a fine-line between neutral action and non-intention,
due to the root of ignorance, imh.
it's not easy to stay aware all the time though.
----
One instance of intention is one instance of kamma. When there
is kamma there is immediate result. Even just one little thought,
although not particularly important, is nevertheless not void of
consequence. It will be at the least a "tiny speck" of kamma, added
to the stream of conditions which shape mental activity. With
repeated practice, through repeated proliferation by the mind, or
through expression as external activity, the result becomes
stronger in the form of character traits, physical features or
repercussions from external sources.
A destructive intention does not have to be on a gross level. It
may, for example, lead to the destruction of only a very small
thing, such as when we angrily tear up a piece of paper. Even
though that piece of paper has no importance in itself, the action
still has some effect on the quality of the mind. The effect is
very different from tearing up a piece of paper with a neutral
state of mind, such as when throwing away scrap paper. If there is
repeated implementation of such angry intention, the effects of
accumulation will become clearer and clearer, and may develop to
more significant levels.
http://www.geocities.com/Athens/Academy/9280/kamma1.htm#meaning
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