People in certain situations require anonymity for privacy. Anonymity is a tool of privacy, not always necessary but certainly necessary in some circumstances.

People in certain situations require anonymity for privacy. Anonymity is a tool of privacy, not always necessary but certainly necessary in some circumstances. Privacy is choosing who knows what about you. Anonymity is a tool to do things in front of some people without them knowing who you are. Clearly if you don't want those people to know that you (your real identity) does those things, you require anonymity to maintain privacy in that respect. > If third parties can access your correspondence you have no privacy regardless of your anonymity. This is false. For example, a citizen in a repressive authoritarian regime can only protest the government "publicly" so long as they are anonymous. You can let all the world know that Anonymous4321 (if you have real anonymity) thinks the government is bad on Twitter and even leak government secrets. Sure, the protest will not be "private" in the sense that it is public, but the privacy angle is that nobody knows that the individual is involved in such activities: they can show up to work at the government the next day after leaking details about the government and nothing will happen to them. Clearly, from the perspective of their real identity, their leaking and protest activities remain "private" from the government even though the government very publicly is aware of the protests and leaks. In the scope of TOR, it clearly helps individuals maintain privacy. I want to keep which sites I visit unknown to even my ISP; that is clearly your version of privacy. On the other end of the connection, I don't want the website operator to know who I am either; this is your version of anonymity. To me those are both just different aspects of the notion of privacy defined by: choosing who knows what about me--with that choice defaulting to knowing nothing about me. Privacy is a broad category, anonymity is a piece of it, necessary only in some circumstances but generally desirable as a default. You can choose to give up your identity, you cannot choose to take the knowledge back from someone.