That's the upshot of what he's saying. But how the cross pollination happens -- crossing over to another plane of thought -- is I think the real point. That is: Cross-pollination between programming languages is a good thing, and therefore we must often force ourself to think outside of our narrow way of thinking in order to find new ways, or else we will dig ourselves into a trench (or find ourselves at a local maxima in the design space of languages).