I feel like this is generally in line with estoppel. If you have been acting like the marriage is valid, you <i>don&#x27;t</i> want the law to give an opportunity for one of the people to say &quot;jk lol that minister was fake&quot; and get out of their responsibilities, especially if it would let them bypass the division of property from an actual divorce. While this seems to be codified explicitly for marriage, my (layman) understanding is that this sort of thing is true in general: if people have been acting like a certain thing is true, and it would be unjust to follow the letter of the law retroactively, you don&#x27;t get to use the law to facilitate injustice, if it doesn&#x27;t bring about any justice to you.<p>New York has a law that you can change your name at any time to anything simply by using a new name without intent to defraud. There are procedures for changing your name, including, oddly enough, <i>restricted</i> procedures on how you can change your last name at marriage (you can&#x27;t pick a brand new last name; it has to be one or the other, or a hyphenated or smashed-together version). But if you just start using a new name, there is the self-referential authorization to use a new name simply because you&#x27;re using it non-fraudulently.