Lyric discussion by BabylonSister 

Cover art for 3 Legs lyrics by Paul McCartney

I do agree that this song has to do with his feelings about John and the break.

In a more general sense I think the song is talking about having everything you should need to; live, succeed, etc. but feel like there's something missing, or holding you back that makes it difficult for you to advance.

A fly flies in (a fly flies in), a fly flies out (a fly flies out) Most flies they got three legs, but mine got one

I interpret the mention of flies in this song to be his dreams/ambitions/feelings. The phrase 'haven't got a leg to stand on' to be in a situation where you cannot prove something, has to do with it too. He cant prove himself/reach his goals without a leg to stand on. This is also why it would be so easy to 'knock him down' because he feels that the things he's achieved are superficial, or that the euphoria of a recent development wont last. You could easily ruin his mood because he knows it, but that would be rude, 'not allowed'. (Or this could refer to John. He lacks the support that he used to provide him)

So in a less general sense i think that Paul is commenting on how he misses having a partner in song writing. It was great to have the freedom to be on his own for a while, but now this is more of a draw back. He doesn't see the same potential in his songs, or feels like they wont 'stick' like the ones he wrote with John.

Well when I walk, when I walk On my horse upon the hill (when I walk the horse upon a hill) Well when I walk, walk walk walk On my horse upon the hill (when I walk the horse upon a hill) And I lay me down Will my lover love me still

Would john be willing to partner even after i was on this 'high horse'? I know I'm really reaching there XD

I also think this is over analyzing. I was mostly just trying to put my thoughts out there for anyone who's curious about this song. I love the song regardless of its intended meaning. Its just so fun!

My Interpretation