The Lord is life itself. We are recipients of life. We give life unique forms because of our unique shapes as receptacles, and through free will we can choose how fully we will receive life. But we don't have life of our own. It follows from this that the more we turn toward the Lord and receive life, the more alive we will be; and the more we turn away the more dead we will be. It also follows that believing life is our own – with all the loves, the thoughts and the power that entails – is actually the antithesis of life.

This is the state of those in the deepest hells, who reject everything of the Lord, even His existence, and claim all life as their own. They are, in fact, only alive because the Lord forces life on them in the amount necessary to sustain existence.

This is, in a sense, what is represented by the rib – which is human, and is alive, but only in the most limited way. When the people of the Most Ancient Church (Adam) wanted to lead themselves and sense life as their own, the Lord had to use that most dead aspect of them to grant their wish. He had to use that bone, which represents our most hellish potential, what we would be if we were to reject the Lord completely.

But then the Lord did something miraculous. He turned that bone into living flesh, into a new person: the woman Eve. This represents that the Lord built that most dead, most hellish aspect of us up into something which felt life as its own, but could acknowledge that life actually came from the Lord, and could thus again be a recipient of life. It wasn't quite as pure as before; people could no longer commune directly with the Lord. But they had what they wanted instead: a sense of self.

The Writings call this – both the rib and the woman – by the Latin word proprium, essentially meaning "as of self." The rib represents the proprium on its own, which is hellish. The woman represents the proprium given life by the Lord.

(Reference: Arcana Coelestia 151, 152, 153, 154, 155)

154. Nothing evil or false can possibly exist that is not the proprium or derived from the proprium. For man's proprium is evil itself, which means that man is nothing but evil and falsity. This has become clear to me from the fact that when the contents of the proprium are presented to view in the world of spirits they look so ugly that nobody can paint any uglier picture. (Those contents vary however according to the nature of the proprium.) As a result when anyone is offered a glimpse of the contents of his proprium he is horrified at himself and wishes to run as though from the devil. On the other hand contents of the proprium which have been given life by the Lord look beautiful and attractive, varying according to the life to which a celestial quality that is the Lord's can be added. Indeed people who have received charity, that is, been made alive by it, look like boys and girls with very attractive faces. And people who have received innocence look like naked small children adorned in different ways with garlands of flowers twined around their breasts, and precious stones in their hair, living and playing in brightest light, with a sense of happiness stemming from the depths of their being.