Because I believe in accountable government. The Parliament we are about to elect has insufficient powers to hold the executive of the EU in check. Aforementioned executive is not even elected. Even the Parliamentarians we vote for today are not personally elected by us - we just vote for party lists. How are we, the people, supposed to hold even our representatives accountable, let alone the executive?
Because I believe in local government. The larger and more diverse the area governed, the more likely it is that a majority will be able to override the wishes of a very large number of people. What is more, any link between the government and people is lost. It is too easy for governments to become self-interested rather than acting in the interests of the people.
Because I believe in small government. Do I really need to pay taxes to fund a whole extra level of government and bureaucracy on top of the city, county and national governments? Not convinced. Essentially, more government=less freedom and larger bills to pay.
Because I believe in history. I can't help reading the whole EU experiment as an attempt to force together disparate cultures with diverse histories. Why should that work? Where else in the world has it ever worked? We can barely hold the UK together, for goodness sake.
Because I believe in monarchy. It would take a long time to explain why, and many of you would think I was bonkers. But I actually believe that constitutional monarchy is the best way to govern a country. I therefore tend to see anything that makes the Crown subject to external (as opposed to internal, national) restraints as treasonous.
So, off I go to vote...