Whether it is arrogant or not, I suppose, depends on the degree of conviction and the manner in which that conviction is expressed. Once upon a time men believed that the sun went around the earth. Now we know different, but could that geocentric view of the universe reasonably be called arrogant? That view was based on what men could see for themselves; Alex's view is also based on what he can see for himself, he has apparently not read any scientific tracts on the possibility of extra-terrestrial life.
Either that or he is pulling all our legs in a more sophisticated manner than usual.
And those of us who are widely read on religious matters know very well that God Is An Englishman.