I have heard that newborns start out believing that they are connected to their mothers. The notion of autonomy does not arrive for some time, and is met with a combination of surprise and fear. The physicality of being attached is clear even to a non scientist like myself, if only from having seen nine umbilical cords before they were cut. It does make me wonder how researchers conducted the interviews with nonverbal subjects but I will take them at their word.
The appearance that we are separate from one another is convincing. A friend suggested that it is as if we are each a wave, all part of the same ocean with only the transitory illusion of being distinct.
"That was a big breaker!" just as it washes back into the undertow.
A case could be made for intending harm to, or feeling competitive with someone who is wholly separate from us. We may feel at odds with the annoying clerk behind the desk at the DMV, or the swimmer in the next lane. But if it is indeed a larger reality that we are all vessels receptive of God's ubiquitous love, lashing out at someone else is as silly as trying to punch the ocean so that it will splash on a sunbather in Marseille.