As Baal HaSulam says in his article “600,000 Souls,” there is actually only one soul, one desire, Malchut of Ein Sof (Infinity). The Light that enters by the Creator is stamped in the desire to receive and this gives it its different qualities but in an opposite form. Then the desire has to rise above its form that is opposite from the Light and resemble it. The oppositeness remains; it actually creates such intensity, such a connection, which enables the desire to enter the Light, to conquer it, and to absorb it. Now there is room for that.
So there is only one desire, and if it comes out differently in words, it is because we attain it in parts, and not even in parts but in tiny grains of self-attainment.
It is like a holographic picture where each of its parts includes all of it (M), but on a smaller scale (m). All the details are kept, but they lose the initial accuracy. There are the first ten Sefirot here, but the clarity is different.
But this isn’t what happens—it seems different to everyone, since everyone has the root of his own soul. In other words, we attain the one general soul in different “angles” by our mutual incorporation in everyone.
It is because the point in the heart is actually above the desire to receive, in others. It is the spiritual root of the individual soul, while the desire itself isn’t worth anything by itself. On the other hand the “others” is the same concept for everyone, it is Adam HaRishon (first man). Thus we all attain the same thing but from different perspectives, until they connect. This is done so that we can help one another in attaining the attribute of bestowal.
From the 4th part of the Daily Kabbalah Lesson 1/9/13, “600,000 Souls”