Horchie's Razor (sometimes referred to as Horchie's Lightsaber) is the term used to describe the policy of assuming all instances of Luke Skywalker are Luke Prime until proven otherwise. If the perspective of the frame is not ideal for determining the existence of Bigger Luke, or it happens to be an NHP, then it is assumed to be Regular Luke.
The term originated in 1995 and was coined in reference to the usenet user known as Horchie421 who thought up the policy and popularized it.
Criticism
Some Bigger Luke Theorists are critical of Horchie's Razor, claiming it is in fact extremely arbitrary. Supporters claim it is no less arbitrary than how Occam's Razor is used.
Trivia
Contrary to the belief of many users, the "421" in Horchie421 does not refer to "TK-421" from A New Hope, but the Cessna 421 Golden Eagle light aircraft. Horchie421 claimed to be an accomplished private pilot in real life, and flew the aircraft many times throughout his career.