Sorry, but I don’t see where it says he has to respond to a woman’s nonsense flirtatious mysticism by lowering his own standard for discourse down to her level. He does not have to tolerate her magical thinking.

I think he drew an interesting correlation between racism and her astrological beliefs that she likely has never heard before, and perhaps will give her some much needed introspection. That is a far more meaningful outcome than whatever else their conversation about astrological signs could have had.