So, ok, this is already better. Income tax data as the base, other things useful to improve them, like Jane Austen novels. Fine, at least a good argument. Why it takes so much time to extract an argument from you? Because you have not made the argument before. What is the point of having a conversation in a forum? To learn something from other people who already know more about this. If somebody has a problem with relativity, I do not spend hours crying "you don't know relativity", I simply explain the points he does not know. In the discussion about the Civil War I have participated as somebody on the other, receiving side, and you have provided a lot of interesting arguments and sources, so that I have changed some of the ideas I had about this time. Unfortunately, you have stopped this. Yes, the problem is not that I would not be ready to accept simple arguments because of some libertarian prejudices or so. I had an issue with the idea that one could make conclusions about the change of the wealth distribution as a consequence of income tax changes, if the information about wealth distribution is mainly based on data about income tax declarations. Because these declarations will change if income tax changes, even if the wealth distribution would remain unchanged. And because the error would be clearly in the suggested direction - higher income tax - avoidance of declaring high income - looks like more equal income distribution. You are the person who claims to have knowledge about these questions, so it would be easy for you to tell us how the researchers like Piketty solve this particular data problem. You could have immediately answered it. As I would have, if you would have had a similar problem with relativity. Instead, you have preferred to waste weeks with meaningless "you don't know nothing" attacks without giving any useful information. All what we have found out is your point that inheritance taxation can, at least at some places, also lead to useful data about wealth distribution. Can. The question if Piketty or somebody else has really used it to solve the mentioned problem with income tax data remains yet open.