Three teachers at a nursery school reported colour-blindness in a four-year-old pupil, so his mother took him to have his sight tested. It was perfect. Perplexed, she began listening closely to what he replied when asked to identify colours. They're all the same, he would say; or, fretfully, it doesn't matter what colour it is. And the penny dropped. Patricia Williams's son, like his mother, is black. The teachers, and most of his classmates, are white - but that doesn't matter, they tell him, we're all the same.

That we're not, that we belong to different races, is the burden of this year's Reith Lectures (R4), and it isn't surprising that it makes us uncomfortable. We think we've passed that stage, that to remind ourselves of people's ethnic origins is to deny their equality and to set them apart. Professor Williams understands this, but she questions it. And when she describes the coach-loads of tourists who flood regularly into Harlem churches, blithely gate-crashing services, arriving late and leaving when they're bored, inappropriately dressed, cameras flashing or whirring - then we appreciate her anger. How would we feel, she asks, if 400 black Americans behaved like that, in an English village church?

This is what she calls racial voyeurism - and at least some of it is to do with a lack of good manners. To summarise the lectures so far would be to oversimplify her arguments, yet they tend towards the same question: how can it be that so many well-meaning white people have never thought about race, and so few blacks pass a single day without thinking about it? She is certainly changing that.

Yet, in England at least, things could be worse. Desmond Tutu's first visit here gave him a heady sense of liberation from the inhumanity of apartheid, as imposed by the infamous government of Dr Verwoerd. He and his wife would ask the way (when they didn't really need to) simply for the intoxicating pleasure of being addressed courteously by a white policeman. South Africa's spiritual leader was talking about his life in Paths to Inspiration (R2): he played some Beethoven and Handel; he read, surprisingly, from Rabbie Burns. Yet he himself is the real inspiration, joyously describing his country as a miracle: "We should have gone up in flames - we were on the brink of it - and here we are, improbably, a paradigm for other nations and a sign of hope."

On Midweek (R4), Agnes Chivara spoke of her work in another part of Africa. With help from Comic Relief she runs a drop-in centre for Ghanaian street children: without such places, they grow up thieving and drug-trafficking, prostituting themselves for gleanings from the grain-stores, without any hope of a better life. Gently she spoke of giving them soap, a sleeping- mat, a chance to rest, literacy classes - and Snakes-and-Ladders and Scrabble, because they're only little and they need to play.

Libby Purves controls her often ill-assorted guests like a benign head- mistress. Where its sister programme will Start the Week solemnly, in half-glasses and a lab-coat, Midweek wears bright hand-knits and swings a gaudy shopping-bag. This week's star was the endearing 80-year old Eileen Halliday who, despite threats and cajolery, refused to sell her old cottage to make way for Sainsbury's. They built their shop around it in the end, and she is delighted with the double-glazing they provided.

People are not so thrilled in Grazeley, a minuscule village which is about to acquire 2,500 new houses. Ruscoe on Five (R5) surveyed the housing market this week, from the bottom of the DIY staircase (concussion guaranteed on every ascent) to the intractable ceiling of negative equity; from the gentrification of Milton Keynes, where ye olde "wavy tin" has been reborn as Tudorised gables, to the annexation of peaceful farmland for vast new conurbations. In the first programme, dealing with homelessness in Brighton, a bright 16- year-old told her story: beaten by a succession of stepfathers, sent from hospital to hostel, robbed by her druggy room- mates, she still got "brilliant" GCSEs, and manages to hold down a job while desperately trying to find somewhere to live. She was heroic.

Also on R5, two football fansexpressed doubt about a penalty in the recent Chelsea-Leicester FA Cup tie. Danny Baker, on The Baker Line, was too forthright by several doorsteps and the network dropped him like a red-hot Chris Evans (the asbestos Talk Radio has picked him up). The Prime Minister, at the end of some aggressive questioning on The Magazine (R5), sounded relieved that someone else was under fire, and expressed sympathy with the referee. He smoulders on.

Now, for two superb programmes. First, Richard Johnson gave a bravura performance as the elderly Ezra in David Pownall's Pound on Mr Greenhill (R3), a play of such witty complexity that I (almost) want to have another go at Pound's prolix poetry. Mr Greenhill was Monteverdi in the guise of a gondolier: "At my time of life," chortled the ageing poet, "I suck up to the ferryman, OK?"

The second took us across the Styx with Orpheus for an utterly fascinating Meridian feature (WS) on Gluck's Orfeo that sent me scurrying back to the music. Psychiatrists and music critics discussed the fact that only when Orpheus is really convinced of Eurydice's death does he produce his loveliest music: from assimilated grief comes pure art.

In hope of another gem, I turned to R2 on Wednesday night for The Organist Entertains, a real anorak of a series. The hot news is that Mr Shuttleworth and the Sutton Organ Society will make us all most welcome on the first Tuesday any month. Overwhelmed with gratitude for such hospitality, I switched off.