In a passage from The future is bright for human, New Scientist 2012.3.5, there is a sentence
Perhaps willfuly, it may be easier to think about such lengthy timescales than about the more immediate future.
I am confused with the word 'willfully'. I have looked up that its adjective form 'willful' means 'sticking to one's own opinion' or 'deliberate', but the adverb form of both entry can't fit the sentence. So how to understand the 'willfuly' here?