How should I translate 认知组成？
I would take


  “我们的思想，是连续不断的认知组成的演变过程。”


and translate it, roughly, like: 

Our thinking, is constituted [组成] by a constantly evolving cognitive [认知] process.

It's not “认知组成” as a set-phrase or even a connected phrase but just two separate words.

Your understanding:


  Our thoughts are evolving(演变） 【in】 a never ending process of cognitive formation(认知组成）.


absolutely works as well.