Researchers at Stanford found that “no” is one of the first 10 words most kids learn, while the word “yes” isn’t even in the top 20. This is because one the primary roles of a parent during their kid’s pre-verbal months is to keep them from doing things they shouldn’t do – a function most parents fulfill verbally as well as physically. So, negation is one of the first abstract concepts many kids learn, and most kids progress quickly from the use of “no” as an expression of rejection to more complex uses as an expression of frustration and then logic. But one linguist found that the children of particularly restrictive parents tended toward more prevalent use of simple negation, while more laissez faire parents’ kids used “no” in a more sophisticated manner. Do with that information what you will.