Back to the original question. I think that this isn't as simple a question as it might at first seem. It might seem fair for everyone to pay the same percentage of their income. Unfortunately, defining "income" has become pretty complicated. Perhaps one should pay a percentage based on what percentage of the national wealth one owns. For 5% to pay 40% of the taxes appears to be grossly unfair, but if that same 5% controls 80% of the nation's wealth, then perhaps it's not so unfair. Maybe the best solution would be a consumption tax (no not for people with TB) that is to say a national sales tax. I don't know. "Fair" share is very difficult to define.