Nothin’ new there, as Einstein said, gravity is caused by gravity. :’)
Never saw that quote. If you have a citation, I’d love to see it.
Einsteins ideas, afaik amount to the following:
GRAVITY=SPACE=GEOMETRY
He didn’t really talk about cause, his results dealt more with observable and theoretical effects based on thought experiments.
His ideas amount to saying that you can nail a picture to the wall without ever saying anything at all about what the nail really truly is, what is the essence of being a nail.
No one can fault Einstein for his view. At the same time, no one can deny that the theory is made more whole by the extensions of Kaluza-Klein and basic quantum evidence.
As it seems to be turning out, his theory might some day be seen as pretty much a good approximation, on par with Newtons ideas.
And in one of the strangest twists in scientific history, I think we will discover that if you take Newton and toss in a little Planck, season well with a bit of Maxwell, you will end up with something better than Einstein.