Part 2: Thus the circle (igul) indicates an encompassing government without differentiation in terms of Kindness, Judgment and Mercy... This is a general point that applies to all the Sefirot. They can all appear in both circular and straight or upright form. This is because, as a hierarchical order consisting of different levels, the Sefirot may be viewed either in terms of the causal chain through which one develops from another, or in terms of the way they actually govern.
In terms of the way the Ten Sefirot manifest level by level, each successive Sefirah is caused by and develops from the one above it. In this aspect, it is of no relevance that one Sefirah inclines towards Kindness while another inclines towards Judgment. For although in terms of government, Kindness and Judgment act in partnership, from the point of view of their development, Judgment emerges from Kindness. From the developmental viewpoint, each successive Sefirah is lower than the one above it, and the Sefirah of Gevurah, “Strength”, develops out of Chessed, “Kindness”. Thus the sages said: “The waters conceived and gave birth to darkness” (Midrash Rabbah Exodus 15:22). In other words, Kindness, symbolized by water, produced Judgment, symbolized by darkness. From this point of view, the Ten Sefirot emerge as ten levels, one below the other. Because of the additional fact that every higher Sefirah bears and carries the Sefirah below it, we can picture them as one inside the other, like the skins of an onion.