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I enjoyed Polly Hudson’s wisdom on marriage (I know it’s taboo – but I’m a big fan of marriage, 9 June). However, I think she was fundamentally wrong when she wrote: “The haters say marriage is ‘just a piece of paper’, which is fundamentally true”. That would be like saying my degree is only the certificate. In both cases the significance is that which it points towards – something no physical object can truly capture.
Rev Martin Joss
Peterborough

• Allow me, a number theorist, to lend support to Ian Harley (Letters, 10 June), and make some sense of the phrase “such fun’’ for Steve Lupton (Letters, 11 June). Many scientists start with fun and enjoyment when young, followed by agony and frustration in their research, but always sustained by the beauty and amazement of their discoveries.
Peter Shiu
Sheffield