FIRST, WE NEED to explore the relationship between these terms, which are slightly different but intricately related. The topic that most excites comment and draws criticism is censorship, which overwhelmingly people instinctively think of as wrong. Yet, when asked about what we should allow children to view or read, at the least we think we should provide guidance for them and if that is not possible we quickly arrive at a point where, we think for the best, some things are concealed from children. Typically, we conceal harmful or illegal content, and the European Union (EU) has a directive for member states to protect minors against such material by restricting it as they think best. Censorship is a cry that is raised in other circumstances, too. We are reluctant to broadcast material on bomb-making, particularly nuclear weapons, biological agents that might incapacitate, injure or kill, or material that might be mentally disturbing for some categories of patients in secure hospitals. The list is easily extended; the question is, where does it stop?

It is clear that we want to limit the range of material that can automatically be banned, and also limit the classes of people who can be denied access to any material they want to see. If we don't agree to such a limitation we are handing over to those with power and coercive authority – usually but not exclusively governments – the freedom to deny access at will as suits them, and without any certainty that the ban will be removed when any temporary need is over. This is just a matter of experience, and that fact brings us closer to the real world where we must consider what actually happens as well as what we intend. If you ban a child from going to the cinema to see certain types of film you may find that you have, apparently, got a compliant child, but it may later turn out that when the child visits friends they watch even worse material downloaded or on videos: policy decisions and the strategies used to implement them do not always lead to the intended results.