Whilst the plot is deep and complex, there is a fundamental theme that conspiracy theories (for which the Grail, Knights Templar and Masons are significant entities) can be construed as a set of alternative, unrelated, connections. The view that conspiracists will read into a connection any conspiracy that is required to be made as long as the joins are logical seems to flow. The by-product is a caution from Eco against a mis-guided logic along the Python lines: if it floats, it must be made of wood! The staggering amount of additional literature that is suggested can be read opens the opportunity for conspiracy unbounded, but should be taken with care. It is a very difficult book to become involved in and is, like a lot of Eco's work, very complex and particularly dry. Saying that, it is worth the effort (and effort it is) to get to the cliff-hanging conclusion. To be read and enjoyed but not taken in a literal sense.