Say it’s dusk and you think you’ve seen a strange, stooping man with a top hat and a cane loitering by a gate, but you soon realise it’s just a tree stump and a bramble. You say to your companion, ‘I thought I saw a weird guy over there.’ You did see that weird guy over there. Your brain thought he was there so it put him there. Then when you approached and new, more accurate, information was detected, it rapidly redrew the scene, and your hallucination was updated.
