If being human means anything, it means using one's mind to make decisions. Taxes rob the individual of choice. Taxation Strains Morality Taxes encourage people to blur the distinctions between business expenses and personal expenses. Taxes also turn most people into plunderers. When the government takes around half of everyone's wealth, it's difficult to avoid taking government assistance all the time.
Taxation is pervasive, mutual plunder.
It turns self-reliance into mutual dependence. It stamps out voluntarism and makes force a way of life. The obvious answer is that as individuals we don't have the time or ability to learn all the skills necessary to produce the goods and services we use. The more subtle but more important answer is that comparative advantage permits us to divide labor and produce more collectively than we could working only for ourselves. There was some disagreement about the nature of comparative advantage at the March Austrian Economics Study Group, so perhaps an example would serve to demonstrate the nature and importance of the phenomenon.