One's company, two's a tradition

I was thinking the other day about literary friendships - strikingly different writers who happen to be writing in the same place at the same time, and are friends with one another. What a lot there are!

Some cases that come to mind:

- Samuel Taylor-Coleridge and William Wordsworth
- William Wordsworth (again) and Dorothy Wordsworth
- Alexander Pope and Jonathan Swift
- The Bronte Sisters
- Percy Shelley and Lord Byron
- C.S. Lewis, J.R.R. Tolkien, and Charles Williams
- Jack Kerouac and Alan Ginsberg
- T.S. Eliot and Ezra Pound
- Mike Moorcock, J.G. Ballard, and Brian Aldiss
- G.K. Chesterton and G.B. Shaw

And then there are the marriages/relationships:

- Emily Barret-Browning and Robert Browning
- W. H. Auden and Chester Kallman
- Mary Shelley and Percy Shelley (again)

There are a couple of things that I find interesting about these writers - or those that I know closely, anyway: their styles are so different that most people seem to have a clear preference for one writer over another. Same here: I prefer Coleridge over Wordsworth, Lewis over Tolkien or Williams, and Aldiss over Moorcock or Ballard.

When the friendships or relationships occur across the sexes it might be interesting to see what sort of attention each writer has got: William has got a great deal more attention than Dorothy, for instance. And though Mary Shelley has garnered lasting fame through her first novel, Frankenstein, none of her other novels (she wrote several more) - or her work as editor/collater of Percy's poems for the benefit of posterity - has got as much attention.

Also, while I personally tend to look at these groups as individuals who happen to know one another, I wonder if there wasn't more to it than that? There's a passage in C S Lewis's The Four Loves, which I've just read, which observes that when, in a group of friends, one friend dies, the survivors lose not just their friend, but the part each had shared with their dead friend. (He expresses it by means of one of those weird algebraic equations: 'When C dies, A not only loses his part in C, but B's part in C as well'.) So while I greatly prefer Lewis over Tolkien, of course, one wonders what each brought out in the other, and how that showed in their books? Are each to blame for the other person's writing?

Any thoughts?