Consider the yeti. Reputed to live in the mountainous regions of Tibet, Bhutan, and Nepal. Also known by the alias Abominable Snowman. Overgrown, in both senses: eight or ten or twelve feet tall; shaggy. Shy. Possibly a remnant of an otherwise extinct species. More possibly an elaborate hoax, or an inextinguishable hope. Closely related to the Australian Yowie, the Canadian Nuk-luk, the Missouri Momo, the Louisiana Swamp Ape, and Bigfoot. O.K., then: on a scale not of zero to ten but of, say, leprechaun to zombie, how likely do you think it is that the yeti exists?