I'm finding this thread increasingly ridiculous. Of course the UK is part of Europe from a geographical point of view, but that's not the main reason for the UK being part of Europe. I'll leave the division of the world into continents to the academics.
The point is that for hundreds of years, the UK has shared and traded philosophical, political and cultural (etc) ideas with Europe. There have been imports of ideas from other continents, but there is a definable European intellectual tradition. To outsiders, we are all European, even if we seem to be more aware of the differences between us.