score:2
The purpose of the precept is to protect you and lift you up in terms of virtue (sila).
Undertaking the first precept of not killing is about changing YOUR state of mind.
It's so that YOU become compassionate, wishing for happiness of other beings, and not have violent and harmful tendencies.
Cultivation of virtues also has the effect of freedom from remorse, which leads to enlightenment. This is according to AN 11.1.
Also, please see this answer.
Upvote:1
All living things feel pain. Feeling pain is a mark of having a life. What seperates insects and humans is that we not only feel pain, but also suffering. Pain is in the physical body. Suffering is in the mind. Buddhism is about the end of suffering. Pain, a physical thing, is unavoidable since we have a physical body in the world and things happen. But the suffering, which is what we make of pain (physical sensations), is in the mind. That is an important difference between pain and suffering.
Upvote:1
I agree with Ruben's answer because it answers correctly from virtue point of view.I also agree with HomagetoManjuShri but I think I need add few more thoughts to it. First and foremost , All beings are capable of experiencing suffering. The suffering is a result of grasping of five aggregates. Different beings grasp at different level. For example if you kill an ant it may not mean much but if you destroy an ant colony it hurts the whole ant family. Moreover Buddha said there is no being which is immune to suffering. Had it been so he would have recommended that state of existence as bliss. There is intelligence everywhere. Insects are also capable of expressing that intelligence and experiencing pain. If we compare human suffering with the suffering of an ant , I think human would like to be an ant because there is so much less suffering. But when change occurs all beings suffer the pain and lamentation which grows with level of grasping of five aggregates. Therefore humans or insect may or may not experience same level of pain. Intensity of pain depends of level of attachment which varies from being to being. So why hurt anyone ? You never know how much pain they feel.