Rather, as explained, all of the substance of the new creation – whether the substance out of which is made spiritual things or the substance out of which is made physical things – is nothing other than the desire to receive. (We have said that the soul is made up entirely of a desire to give. Yet, that is only due to the repairs that occur when the reflected light is enclothed [in the soul. That light] is received from the upper worlds, from where it comes.
I explain the matter of enclothing in my Petiḥa Leḥokhmat HaKabbala in chapters 14–16, 19. Still, the essence of the soul remains a desire to receive. See the sources there to understand.) For the thing that distinguishes one example of a thing from another is not its substance, but its will.
For the will in every essence produces needs, and those needs produce thoughts and knowledge to the same degree [as the needs]. Then, the creature can [go out and] acquire what it requires to fill its needs.