The external world is cognised through direct perception, etc. Therefore, all that is capable of being pointed out as this or that, or of being indicated by a name or a form, is subsumed by the idea of “creation (srishti)”. Creation means an act, a result.
What then was before that act?
Before this, the Atma alone was
Idam agre, Atma eva aaseeth.
The world was a latent product; later it becomes patent. In the latent stage, it was unmanifest in the Atma itself. When the urge to manifest appeared, the multiplicity of names blossomed forth, and all this variety arose to view. Being perceptible by the senses —this is the test of manifestation.
Name is fundamentally sound, manifesting as word. In the statement “this is Ranga”, when the sound Ranga is produced, the listener turns to the person indicated and identifies him as Ranga. The word and its meaning are inseparable. The two were both nonexistent before creation.
Therefore, the Atma and the unmanifested creation (jagath) were unreachable by the intelligence and the world that it fashions. After creation, since name and form became the essence of all this, everything can be grasped by words and meaning. The non-dual that was, is, and will be is the Atma. The multiple manifestation of variety proliferating in name and form is the creation. But, basically, it is just one unique substance (vastu).