ABSTRACT
We began this book by remarking how very hard it is to talk systematically about politics without talking about the policy “positions” of key political actors. This is why “spatial” models of party competition have been so influential over recent decades. As we noted in Chapter 1, however, the notion of a policy space raises some unexpectedly deep intellectual issues when we start to think carefully about it. The most important conclusion to be drawn is that, just as there is no such thing as a perfect map of the physical space in which we all live, there is no such thing as the perfect map of any real world policy space. In each case, different maps are suitable for different purposes. We have not therefore, in this book, been in search of some elusive Holy Grail of a unified empirical policy space for use by political scientists. Our result, if anything, indicates that such a goal is unattainable.
