The poor don't get taxed if the special tax is progressive (or non-existent at lower levels of income/wealth). Of course, the argument that such a tax being eff

The poor don't get taxed if the special tax is progressive (or non-existent at lower levels of income/wealth). Of course, the argument that such a tax being effective is impossible these days due to contemporary mobility of wealth may well be true. That still doesn't amount to a special tax on the poor, and I'm sure you realize Piketty wouldn't advocate for that, whether or not you agree with his positions.