Paul's 500 witnesses.

[Silver]

That made no sense. If you are born healthy your brain is constantly building new neurological pathways as you grow to an adult. A newborn cannot suddenly be as smart as an adult. If your brain didn't grow as you did you would not be able to learn things. 

Intelligence is an evolutionary attribute, it is our species ability to be curious, but that does not make a newborn as in individual having the ability to adapt to all information and understand it at birth. Learning takes time, you don't have adult knowledge as an infant.

I think he is referring to the I.Q., which does not change.