That's totally irrelevant. Dullard is not arguing about Keynesian economics, he's trying to run with the argument that raising interest rates INCREASES inflation. That is the point on which he is in disagreement with almost the entire field of economics.
The biggest problem is that people don't see economics as a series of cycles even though human activity is highly cyclical. Just look at fashion trends. Fashion is never a straight line, and things that were popular decades ago suddenly become popular again. That cyclicality applies to everything humans do, and economics is no exception.
It's not accurate to say lower interest rates
only cause inflation or that they
only cause deflation. They cause both, but not at the same time. Greenspan dropped interest rates to 1%, and it caused extreme inflation. Housing prices doubled within a few years. Of course, every bubble pops eventually, so this lead to severe deflation. Housing prices were cut in half. Do you see how that cyclicality works? The price doubles due to the low interest rate, but it reverts back to the mean through deflation.
Higher interest rates are no different. The immediate effect of high interest rates would be extreme deflation like we saw in 2008. Tons of mortgages and other debt would be unaffordable, millions of houses hit the market, business go into liquidation, prices fall dramatically. The mean reversion in this case would be when the economy adjusts itself and gets going again. Instead of the economy favoring people who borrow up to their eyeballs then file for bankruptcy, it would favor people who save their money.
Right now, retired people are cutting expenses to the bone because the interest income they receive from bonds barely keeps up with inflation. The richest generation in human history is forced to cut spending as much as possible because the interest rates are low. Do you think that would cause inflation or deflation? Probably deflation. Central bankers are complaining about low inflation, and then they invoke policies that would logically cause deflation. Of course there's deflation. If baby boomers are not spending, and young people don't have jobs, where is the demand supposed to come from?