Religions just posit a purpose, science gives evidence of organization and planning. It's a black box though, we can observe the effects of the organization, we just can't see inside the box to figure out how or why it's organized in this way. Sort of like figuring out DNA is a Double Helix, it's too small too actually see the structure. The way it was figured out was by bouncing Xrays off crystals of a DNA hydrate, which gave a reflection that if you analyze mathematically is characteristic of a helix. Very neat trick actually, which Rosalind Franklin should have received the Nobel Prize alon with Watson, Crick & Wilkins. She was the crystalographer.

Anyhow, DNA's structure and how it works is something that was inside the box we didn't know before 1953, now we do. There's a whole lot more inside the box we still have little clue on, but in a million more years we might have had a shot. How the brain works to organize thoughts and emotions is pretty much a mystery, besides identifying a few areas in the organ responsible for various tasks. Better understanding that might have given a clue as to the purpose of the organization necessary to build it. Not gonna happen though.
RE