The purpose of the patent system is to promote the progress of science and the useful arts. It does so in two ways: First, it incentives invention by providing inventors exclusive rights to new inventions for a limited time. Second, it encourages disclosure and provides a database of information in the form of millions of technical disclosures about all sorts of topics. It is amazing what you can learn from patents, and one such fun fact appropriate for today is that the last name of Punxsutawney Phil, the hero of the day, is Sowerby! This fun fact appears in U.S. Patent No. 10296823, which in Col. 34, lines 21-30, explains the difference between connection and dependency with a Groundhog Day Example: