Invisible Pink Unicorn is a parody religion that highlights arbitrary and unfalsifiable nature of religious belief similar to Einstein's pen which asserts that people must provide proof for a belief instead of others proving otherwise..
She is a rhetorical illustration used by atheists and other religious skeptics as a contemporary version of Russell's teapot, sometimes mentioned in conjunction with the Flying Spaghetti Monster. Russell's teapot is an analogy, formulated by the philosopher Bertrand Russell (18721970), to illustrate that the philosophic burden of proof lies upon a person making unfalsifiable claims, rather than shifting the burden of disproof to others. 
