The Immaculate Conception

I don't consider it to be a knockdown proof of the Immaculate Conception, but I do think it's a strong argument that can be a valuable part of a more cumulative case. God is not some creepy old man in the sky who impregnated a scared 13 year old girl. He's the perfect all powerful creator who gave Mary grace to be free from all sin so that she could freely consent to give her body to God and cooperate with his plan to save mankind. But given this objection, I think we still need to be careful not to overstate this argument.