Two envelopes problem
A simple non-mathematical resolution is that no information has been gained by selecting the first envelope. Since no information about the contents was available before selecting the first envelope switching envelopes is a neutral act.<p>While this sounds like just a lazy intuitive explanation, it calls out the key component - a lack of information about the outcome - that can help avoid the paradox in more complex situations.<p>This is in contrast to the three-door problem where information is gained by opening the first door. <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Monty_Hall_problem" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Monty_Hall_problem</a>