He had some serious encyclopaedic recall, but that didn't come innately, he still had to fill his head with all that information.

Senku paused and considered Siebren's words, one finger over his lips, thumb under the chin as he thought for a moment, as though parsing it. He didn't know all of the words, but he could guess at the context.

"We can do this whenever you're free, I'm not that busy on the train." He said, and despite the fact he was constantly doing something he believed that to be true.