The More the Merrier

What exactly is the role of the word "the" in this common expression?

The Merry Pranksters take a ride through the streets of San Francisco on The Bus, decorated for the Acid Test Graduation, October 1966.

This week, our listener Nick Burns writes:

“I’d like an episode on the ergative-absolutive language alignment if possible, because my understanding of it is weak! There’s also a lot of cool languages that use this alignment, such as Basque.”

Nick, I don’t think I could get a tasty episode out of ergativity alone, but it’s important for language folks to understand it. The truth is, the way it’s presented outside of academia, if at all, tends to assume that laypeople find the same aspects of it interesting as linguists do, which is not necessarily the case.