His argument, as stated, is a use of the Nirvana fallacy. But it can certainly be re-phrased and re-worked into something substantial. The general sentiment isn

His argument, as stated, is a use of the Nirvana fallacy. But it can certainly be re-phrased and re-worked into something substantial. The general sentiment isn't completely without merit; people will always exploit loop holes in the tax system. But to say there isn't any point in closing this loop hole or that loop hole because people will just use another is an assertion, not an argument. You need to provide evidence to support this claim. Maybe those other loop holes are more of a hassle, or require substantial initial investment to take advantage of (like re-structuring your company to incorporate in a different country), or don't shelter as many assets from taxes. The point is, you need evidence to back up the claim. > The qualitative fault I'm trying to point out is that trying to tax 'rich people' is a failed attempt because no matter how effective you can implement your tax measures, at the end of the day people can move to other countries and your own country starts to suffer more than it benefits from the increased taxes. That's more of an argument against taxes in general, isn't it? You tax people high enough and they'll leave. There's a certain "sweet spot" at which you tax people just enough to provide good services without making people leave. I wouldn't dispute that. But for that to be a valid argument in this case, you'd have to provide evidence to show that closing these loop holes puts the tax burden of people above that "sweet spot."