Today I'd like to talk just a little bit about the not-knot merger. Way back in the day, there was a difference in the pronunciation of the words "not" and "knot". The "k" in "knot" wasn't a silent hanger-on, it actually did something. If you said the word "knot", you'd pronounce the K, and maybe (I'm really just guessing on this) it would have sounded like "Kh-not" or [knot] or something like that. Same was true for things like "knee" and "knight". All those words had a "k" sound in front of them, (and the ends were a little different too in most cases). Over time, the English language, as all languages do, smashed some sounds together, forgot about others, and just threw a few extra sounds in other words just for giggles. As English changed, the "k" sound was left out more and more in "kn-" constructions, until it finally produced the same sound, and "knot" and "not" became indistinguishable in pronunciation. Even though the sounds changed over time, the spelling remained exactly the same.

This same process happens constantly, and is happening right now. We're dropping the yod, the "yuh" sound, from a lot of our words. Think of an british dude saying "tune" (tyune), and an american saying tune (toon). We still keep the yod in a few words like "fume" "hewn", but for the majority, words like tune, coupon, dune, misfortune etc. have lost the yod.

So yeah.

That also shows that there are a lot of things that are nonsensical and confusing simply because they're relics of another context and environment. Aftereffects can last thousands of years.