This is how this board works in a technical sense:
you log in, it looks at your username, and then converts your password via a one way hash and then takes that hash and goes to the magical database. it looks at your login name in the database, and then looks at the hashed password value that is there for it. if what you passed in is the same as what it finds in the database, then it authenticates you and sets a cookie. in the cookie is your username and your password hash. this allows you to view pages as logged in without having to keep logging in - there is also likely a session set for you.
Then you have the option to browse, post, do karma, etc etc.
Browsing sends a number into the database that represents the thread that you want to see. It finds all the threads that match that number (the number for this particular thread is "148353") and returns that and formats them so that they are all pretty for us to read.
Posting and replying to a thread are similar only they insert into the database. if it is a new thread, then it gets a new number that isn't there yet, and if you are replying, then it gets the number of a thread that exists and then it notes that post is the Nth number of that thread so that it can order it when it comes out.
Even PMs work the same way - but it (should) authenticate who can see it on either side, whereas the normal boards allow anyone to see posts (aside from the special ones that also authenticate - like the pay sections and the mod board).
Karma too works in this way. it looks at what post you are looking at, and it looks at what user ID you are, and who you want to send it to. It used to let you go all willy nilly and just keep giving it to the same person - it did a cursory check at various points as to how much you have given out and such, but they added more once people figured out ways around it - either via looking for it or serindipity. whether or not they used to have the feature, they have since indicated that they do have this feature now - when you give karma, it adds the ID of the person that gave it with it in the database.
they don't display this, b/c the point of karma isn't to get rude or pleasant messages from someone - that is what PMing is for. the point of karma is to reward or punish you for your deeds, whether good or bad, or if you are an unjust god, then you hurl insults in an arbitraty manner.
there is more complexity to it - but the point in the end - "we have the technology" - but the bigger picture is that what you are arguing for is both silly and against the grain of what karma should be.
now if you want to add a new button that says "send me a message and also increment/decrement some arbitrary number and know who did it" then that would be what you are proposing.
but that is in no way karmic - that is just a pm with a score associated with it.
just a reminder - this is all on a server sitting somewhere. all automated. we sit at various points about the world and bang on keyboards and get varied ressults on our screen depending on how the predefined patterns on the server react to what we bang on....
meaning - there is more to life than caring what that server thinks of us.
there really is no person on the other end - it is a server, there are an infinite number monkeys banging on it - but the karma is not a true value of your worth or how they feel of you, it is solely a side effect of actions taken against code on a server.
stand back and open your eyes, for you have much to see.
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