Summary: In 480 words, this short entry defines public opinion, explains some of the many problems inherent in discussing public opinion, and briefly introduces the concept's political significance.
The entry defines public opinion as a specific range of views held by a significant portion of the population about a controversial issue. In the very first sentence, the entry emphasizes the ambiguousness inherent in any discussion about public opinion. What or who is the public? Does all the public have opinions on every issue? Which opinions count or will be taken seriously? The entry offers some criteria, which are incorporated into the definition of public opinion. It is best to think of 'the public' as the total population. Conceptually, opinions require two elements: they must be about a contested issue and they must be rationally defensible.
Public opinion expresses itself politically as the majority. The link between this expression and actual influence over government policy is tenuous, although public opinion does seem to function effectively as a limit on government action.