"Plunging" or Challenging Yourself in a New Enviornment On television I recently heard about a technique related to Buddhism called "plunging," where "you go somewhere completely unfamiliar, somewhere that has nothing to do with your usual way of thinking." The context of the quote involves a Zen monk who lived among the homeless for a time. As a student of Zen Buddhism this idea interests me a lot, but I couldn't find any reference to it on the internet or in my books. Is there a better name for it and is this a real concept or was this just made up for the show?
I have never seeing this term as a concept in Buddhism nor Zen. To the best of my knowledge, the closest formulation of something in that vein are the specific instructions to practice samadhi in the Vishuddhimagga targeted at people with distinct temperaments  -- which is kind of a compilation of pedagogical strategies developed at the time. Example:

&quot;A suitable lodging for one of greedy temperament has an unwashed sill and stands level with the ground, and it can be either an overhanging [rock with an] unprepared [drip-ledge], a grass hut, or a leaf house, etc. It ought to be spattered with dirt, full of bats, dilapidated, too high or too low, in bleak surroundings, threatened [by lions, tigers, etc]. with a muddy uneven path where even the bed and chair are full of bugs. And it should be ugly and unsightly ...&quot;
A suitable resting  place for one with hating temperament is not too high or too low, provided with shade and water, with well-proportioned walls, posts and steps, with well-prepared frieze work and lattice work, brightened, with various kinds of painting, with even smooth soft floor, [...] smelling sweetly, of flowers and perfumes and scents set about for homely comfort, which makes one happy and glad at the mere sight of it.&quot;
-- Visuddhimagga, Chapter III