Janet Yellen had the perfect response to a question about Donald Trump causing a global economic crisis

Federal Reserve Chair Janet Yellen spoke in Philadelphia on Monday.

The topic, of course, was the economy and monetary policy and when the Fed will raise rates next. (Short answer: it's unclear.)

But following Yellen's prepared remarks she was asked questions by the crowd at the World Affairs Council of Philadelphia.

The final question put to Yellen, naturally, was about presumptive Republican presidential nominee Donald Trump.

Yellen was asked a question regarding commentary this gentleman - who is not a member of the media - had heard on the morning and Sunday political shows (think "Meet The Press" and "Morning Joe") about the potential for a Trump presidency to cause, "an economic crash all over the world" because of how the rest of the world sees Donald Trump. Namely: as a loose cannon.

This gentleman asked simply, "Is this a possibility?"

Yellen laughed, and said only: "I'm sorry, I've got nothing for you. We're focused on our jobs."

Trump, we'd note, said back in May that in business he has borrowed knowing that you can "pay back with discounts," which is another way of saying your lenders won't get all their money back.

And while issuing the high-risk debt of a casino company might allow for this possibility, Trump floated this idea with respect to US government debt, considered the safest and most liquid non-cash asset in the world.

Josh Barro wrote at the time that this is crazy and not to be joked about. But then again Trump is in Josh's words, the "tail risk candidate." So if there ever was a candidate that possessed the desire to willingly launch the global financial system into crisis, it would be Trump.

But realistically this probably won't happen even if Trump is elected president.

Deciding to simply not repay the US' financial obligations - which are at this point infinitely fundable given 1) our ability to print money and 2) the financial market's unfailing trust in the government's to pay back its debt - is an insane decision even for a candidate that might preach more fiscal discipline from the government.

Any sensible businessman would know better, and so we're all probably better off heeding Yellen's advice and just focusing on our jobs.