TONY: Maybe they should stop seeking new horizons a while and just play with what they know. Through play, they may discover hitherto unknown properties that will be the answer they need.

dhw: I think they ARE playing!

TONY: I mean play as children ply, with few assumptions, just seeing what happens and observing. Kids don't generally analyze ahead of time when they play, and imagination becomes the possibility space and the playground the test lab.
[…]

TONY: I think we are using the word "play" differently.

dhw: Yes, it depends what kind of play you mean, and maybe I've misunderstood your reference to children's games. As I see it, when children play, they use their imaginations and often pretend that something is real, though it isn’t. We take what we think we know, and pretend that the "unknown properties" we extrapolate are real: hence the many theories believed in by theists and atheists alike. That is why I think they – whoever they are – (and we) are “playing”.

TONY: All creatures play, and through play we learn about socialization, our environment, what works and what doesn't. But this was already written, and explains it elegantly:
Psychology of Play

No quarrel with any of this! I thought you were suggesting that scientists should adopt the same attitude as children at play, drop their assumptions and use their imagination. I think they all use their imagination, but some allow their imagination to be directed by their assumptions!