I want to know the answer to the following question:
In pre-buddhist early Brahminic texts there is no evidence for what?
All the background I'm provided with is that "Having argued that the cosmological statements in the Upanishads also reflect a contemplative tradition, he argues that the Nasadiya Sukta contains evidence for a contemplative tradition, even as early as the late Rig Vedic period.". Is that enough to answer the question?
Answer: no