For some reason, Benjamin Franklin is known for doing, like, everything first. This is no exception. This little brain quirk is known as the 'Ben Franklin effect' and it refers to the fact that if you get someone to do a favour for you, they'll actually like you more. Yeah, you read that right. Don't do a favour for them, get them to do one for you. From the horse's mouth:
I therefore did not like the opposition of this new member... Having heard that he had in his library a certain very scarce and curious book, I wrote a note to him, expressing my desire of perusing that book, and requesting he would do me the favour of lending it to me for a few days. He sent it immediately, and I return'd it in about a week with another note, expressing strongly my sense of the favour. When we next met in the House, he spoke to me (which he had never done before), and with great civility; and he ever after manifested a readiness to serve me on all occasions, so that we became great friends, and our friendship continued to his death.
Now, that there is Ben Franklin, writing about a time that a new member of the Pennsylvania General Assembly (the legislative authority for the state) didn't like him. So he asked him a favour and the member started to like him. Franky goes on to note:
This is another instance of the truth of an old maxim I had learned, which says "He that has once done you a kindness will be more ready to do you another, than he whom you yourself have obliged"
Cognitive dissonance is a source of trouble for the brain. Essentially, when something you do goes against your brain's internal image of you, the brain freaks out and tries desperately to justify it.
This is thought to be an example of that. Our brains have expectations about how we act when we don't like someone. It also has expectations about the kind of people we do favours for (our brain builds expectations about everything). You probably don't do favours for people you don't like and do do favours for people you do like. So your brain starts to slide the person closer to the latter category to save itself the bother of trying to create a new category of people - assholes that you do favours for (the brain is all about taking shortcuts).
Now, some subsequent research (and there's plenty of it) has found that this effect works for people we're neutral about too. Your brain appears to just slide people closer to the 'I like them' category if you do favours for them. So, I guess now I know what happened to inspire Chris Brown's song. Never did understand those lyrics until now.
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