This is the 1494th most frequent Turkish word.
düşünen
"Thinking" or "thoughtful."
Here, "düşünen" is used as an adjective derived from the verb "düşünmek" (to think), describing the noun "insan" (person).
Düşünen insan geleceği planlar.
A thinking person plans for the future.
In this context, "düşünen" functions as a verbal adjective, describing the leader's characteristic of thinking or being thoughtful.
O, düşünen bir liderdir.
He/She is a leader who thinks.
Here, "düşünen" modifies "beyinler" (brains/minds), emphasizing the act of intellectual thinking as an important aspect.