The premier of New South Wales, Mr. Carr, wants a cap on Australia's population - probably at a level not far from the present 18 million. In an interview with The Weekend Australian, he said those who argued that Australia should aim for a population of 30 million or 50 million were 'totally scientifically illiterate.' To achieve the goal implied by Mr. Carr of stabilizing the population would require maintaining the low immigration levels of recent years or even reducing them.

He said any intelligent person who looked at the evidence had to be persuaded by environmental limits on population. 'The debate ought to be about the carrying capacity of the continent - a continent that has lousy soils, fragile vegetation, and depleted and degraded river systems,' he said.

He also argued that the most successful economies in the world were those such as Japan, Germany and Switzerland with stable populations.

An inquiry chaired by federal ALP president and former science minister Mr. Barry Jones last year found that a stable population of 23 million could be achieved with net migration of 50,000 a year. Immigration in recent times peaked in 1988-89 with a net figure of 157,400. In 1992-93 net immigration was 30,500 with 49,600 the following year.

Mr. Carr triggered a debate last week when he argued that immigration should be cut on environ-mental grounds. He has gone further this week in challenging the post-World War II orthodoxy that immigration and rapid population growth deliver net economic benefits - still the basis of Canberra's immigration policy.

Mr. Carr wants to force Canberra to do what successive federal governments have avoided set a target for Australia's population. Those who have advocated targets range from environmentalists who say the population should be allowed to fall to 7 million or lower, to economists and some business people who want Australia to have 80 million to 100 million people.

Mr. Carr also has challenged political orthodoxy by offending the ethnic lobby. In the interview he defined his position in the debate as 'a supporter of multi-culturalism, a fierce opponent of racial prejudice, yet someone who is aware of the ecological limits Australia is up against.'

'I am arguing for a population policy while rejecting any element of discrimination in immigration policy. It is an intelligent mix which people understand,' he said.

I have been encouraged by the response I have had, particularly from people with migrant backgrounds, people who know exactly what I'm talking about. I am happy to become the first Australian leader to say we ought to debate Australia's carrying capacity.'

Asked about the attitude of other countries, including our neighbors, that Australia was under-populated, he said people overseas held this view only 'until they fly over and see how much of it is desert.'

Asked whether a low population argument was sustainable in the long run with a still growing world population, Mr. Carr responded 'We have got no alternative. If you focus on the Murray-Darling river system and if your soils are blown across the Tasman when the weather turns bad and if your marginal farm land is collapsing, you just have got no alternative.'

Mr. Carr said he did not know what the optimum population level was for Australia but he would be exploring this in a detailed paper he had commissioned from his department. He stressed that this study would go further than his concerns over the population limits of the Sydney basin. ;