We discover that all human beings are just like us, so we are able to relate to them more easily. That generates a spirit of friendship in which there is less need to hide what we feel or what we are doing.
Certainly we do not need quantum mechanics for macroscopic objects, which are well described by classical physics - this is the reason why quantum mechanics seems so foreign to our everyday existence.
If you find a neighbor in need, you're responsible for serving that neighbor in need, you're responsible for loving a neighbor just like you'd like to love yourself.