"He then argued that boys outperform girls on maths and science due to genetic difference rather than socialisation. He gave the conference an example from his own experience: a story of giving his daughter two trucks, which she treated like dolls, calling them mummy and daddy trucks."
If you supposedly can read that much into the way a kid plays with toys, I wonder what Larry Summers would think about the way I treated my dolls as a child. "Oh no, Barbie! Don't jump! You have so much to live for!"