Could all above comments be concluded by this?
In case 1, the intention is to only WALK and meditate, it has no direct connection to any other beings (including the insect etc), we can safely say the dying of the insects is purely collateral damage, we can coarsely commpare it to a bolder rollong down a hill (the boulder just moves because of gravity, it has no intention towards any being or anyTHING). This explanation makes much more sense.
Here’s another case similar to the one above: Some people like to guilt other people for eating meat, since it causes suffering to the animal, but they might not realise even consuming vegetables kills animals (there are bugs, worms and snails killed in the process from planting to harvesting); but the dying of the bugs is again, COLLATERAL, we just consumed the stuff and indirectly cause the unwanted effect.
In case 2, the intention it to INFORM other party, which directly affects the person B, we cannot say it is collateral damage; A knows B will probably overreact, so kamma is indeed created.
In case 3 the same happened; Grandmother want to effect baby to not suffer (grow up healthily), but due to ignorance or lack of knowledge about nutritions she caused more suffering instead (failed kidney). Kamma is definitely created.
It all comes to intention AND parties involved. If the intention involves other party directly, and also directly causes more suffering to them, then we can safely say there is he/she will be responsible in the future. Do please discuss this issue even further.
Thank you very much for creating this website, I always find ‘holes’ in people’s view everytime, especially during a 3 year period where I spent a good portion of my spare time studying many major religions and philosophical view, until I stumbled upon this website when researching Citta and Abhidhamma. Not only I found myself automatically sucked into contemplate deeper and deeper concepts, I also felt a burst of joy everytime I stumbled upon newly “rediscovered Dhamma concepts” and after a quick contemplation realised it is in sync with my previous existing Dhamma information, truly the world view puzzle is heading in the right assembly direction.