The Big Question is broadcast on Saturdays on BBC World Service radio. These are the 'big questions' featured so far:

17-04-04 What is religion?
24-04-04 What does it mean to be religious?
01-05-04 What is the legacy of the Enlightenment?
08-05-04 Have we lost faith in science?
15-05-04 What is cloning?
22-05-04 How big is the web?
29-05-04 Are we too many?
05-06-04 Are we the wrong age?
12-06-04 What is history?
19-06-04 Can we trust history?
26-06-04 Iraq: Is history repeating itself?
03-07-04 Why do people smoke?
10-07-04 Why do people have unsafe sex?
17-07-04 Can people change their sexual behaviour?
24-07-04 What is happening to the Earth's weather?
31-07-04 How have rising temperatures affected our world?
07-08-04 What is democracy?
14-08-04 Does democracy work?
21-08-04 What inspired Marx?
28-08-04 Can there ever be a classless society?
04-09-04 Why are Americans So patriotic?
11-09-04 What is religion? - repeat of 17-04-2004
18-09-04 What does it mean to be religious? repeat of 24-04-2004
25-09-04 Why does the Amazon matter?
02-10-04 Does aid work?
09-10-04 What is Free Trade?
16-10-04 How fair is Free Trade?
23-10-04 What swings elections?
30-10-04 How big is the web? repeat of 22-05-04
06-11-04 Can we ever beat slavery?
13-11-04 How much does the world rely on oil?
20-11-04 Can we live without oil? 27-11-04 Why do people have unsafe sex? repeat of 10-07-04
04-12-04 Can people change their sexual behaviour? repeat of 17-07-0411-12-04 Can fast food ever be healthy?
18-12-04 How safe is the food we eat?
25-12-04 What is music?
01-01-05 Why do people smoke? repeat of 03-07-200408-01-05 What is money?
16-01-05 Why do we get into debt?
22-01-05 Should Africa be left alone?
29-01-05 Who needs migrant workers?
05-02-05 Is too much religion bad for you?
12-02-05 How important is America?
19-02-05 What is music? repeat of 25-12-0426-02-05 Is this China's Century?
05-03-05 How much choice do the people of China have?
12-03-05 Should we worry about extinction?
19-03-05 How easy is it for refugees to return home?
26-03-05 How easy is it for returnees to resettle?