[andrelgomes]

Another term for this is the Hegelian dialectic [0]. Very similar to your term playful association but it describes that the "first" old idea, the thesis, allows there to be a counter idea, the antithesis. These two counter ideas morph into one idea, the synthesis. A consequence of this term over playful association is that these New Ideas are more tangible and have less sense of randomness.

An example of this playing out - First came Disco, the thesis. People who didn't like Disco came up with Rock, the antithesis. The combining of those two became Pop, the synthesis. And the music timeline continues (don't overthink the music choices I'm completely guessing)

[0]: https://en.wikipedia.org/wiki/Dialectic#Hegelian_dialectic