Bhagavad Gita, Chapter 7, Verse 4

Earth, water, fire, air, ether, mind, intellect, and egoism: thus is My Prakriti divided eightfold.

Even the mind and sense of self are named here as part of the material picture, not something separate from it.

This lists out the material world in real, specific terms, physical elements alongside mental ones. Mind, intellect, and ego aren't treated as somehow above matter, they're described as part of the same energy everything else is made of.