> the founders did not want a two party system.

Well, they said they didn't want a factional system, then they built rules which guaranteed two factions, modelled directly after rules which had done the same elsewhere, and all while organizing themselves into two factions which were visible in nascent form in the first national elections under the Constitution and well solidified by the time Washington was to be replaced as President.

So, do you listen to their words, or their actions? The founders were, to all evidence, a lot like politicians of today, publicly cursing the ills of partisanship while deeply engaged in it, mostly as a rhetorical device against the other party.

Of course, the math says that with the current voting system, any third party that emerges as a major force will always consume one of the existing major parties, leading the nation back to a two party system. I wonder why people always ignore this inconvenient theorem.

Most people don't understand that intuitively, I think.

To which theorem do you refer ...?

It's called Duverger's Law.

https://en.wikipedia.org/wiki/Duverger%27s_law