Bernie Cox West Ryde Already we are seeing increasing violence, congestion, housing shortages and mortgage stress in our big cities. Migrants have been invited to add to our economy and most have become hard-working contributors to society. Some diversity and multiculturalism is stimulating, but continuing population growth could have negative impacts on ethnic groups and our cultural integrity. They could become victims of racial tensions. We depend on science to justify the development of mining, agriculture and industry, and our ''carrying capacity'' should also be scientifically assessed. Farmers know that overloading paddocks with livestock brings negative returns, and so it would be if our land was overloaded with people. A population of 36 million by 2050 should not be based on a whim of Kevin Rudd, or ad hoc immigration, but on independent scientific studies and feasibility reports. It is not only environmental capacity that should be assessed, but also our social and economic capacity to cope and benefit. Our main source of population growth is from immigration. Priority should be given to the welfare and future of existing citizens, not those overseas.

Vivienne OrtegaHeidelberg Heights (Vic) Having a minister for population is a start. The next step is to recognise that population growth is stressing our environment and causing social problems, with little or no offsetting economic benefit. The only responsible goal is stabilising our population and consumption at levels that can be sustainably supported. Ian Lowe President, Australian Conservation Foundation, Marcoola (Qld) Larry Tofler (Letters, April 5) asks how Australia will benefit from further increases in population. I presume Tony Burke will be seeking to manage a planned increase in younger folk to redress the imbalance in the growing proportion of older folk like me. David McKay Bathurst

Silly you, Larry Tofler. Of course there are benefits: 100 more workers means 100 more taxpayers to provide the infrastructure and services costs brought on by the need to cope with the additional population, to manufacture the additional goods they will devour and to ensure the additional economic growth necessary to cope with and provide for the next 100 - and so on ad infinitum. Richard Birrell Waitara There will be disadvantages and challenges of a larger population, but these should be seen in terms of overall costs and benefits. In 1947 Australia had a population of about 7 million; today it is more than 22 million. But our standard of living has risen considerably since then. While acknowledging the disadvantages raised by Mr Tofler, I would rather live in Australia today, with a higher population and higher standard of living, than return to 1947. John Chippendale Marsfield

Schools guilty of letting students glory in failure It is not only helicopter parents who refuse to let children fail (Letters, April 5). The state school system has been integral in creating the paradigm that failure is negative and destroys self-esteem. This has led to disastrous educational outcomes and behaviour problems. In only the most extreme circumstances will a student be kept down a year for failing core subjects. The students know they will progress through school even if they fail every subject. Therefore, they don't bother working or listening, or respecting teachers or fellow students who may want to work. Instead school has become a social club, the classroom an opportunity to publicly glory in failure. As a teacher this is the reality I face every day. Students who have failed every year of secondary school arrive in year 11 thinking they can pass by doing nothing, though they are unable to construct a sentence or read more than a page in a novel without getting bored.

We need to return to keeping students down who fail, while increasing support for students with genuine learning difficulties. Failure is a great motivator. Rohan Wightman Parap (NT) Megan Cliff apparently feels her children won't be able to keep up with homework unless she helps them (''Learning from failure provides valuable lesson'', April 3-4). As a single mother of two, I have never done an assignment for my children, now in year 10 and year 12. My assistance has progressed from the purchase of A3 coloured cardboard, glue sticks and coloured pencils to maintaining computer and internet access, and occasional proofreading. The bias that comes with too much assistance is likely to inhibit the child's ideas, producing an outcome that reflects neither the ability of the child nor their level of maturity.

There will undoubtedly come a time when parents are not competent to provide assistance, unless we are up to date with the curriculum to the level of HSC chemistry or extension maths. When this time comes, surely it is better that our children can continue unassisted, rather than find themselves floundering at precisely the time they need to focus and achieve. My children are much better off having learned how to approach their tasks independently. They achieved more than they would have with my help - they are infinitely more creative and smarter than I ever was. Jacqueline Maroney Lane Cove Not everyone needs to go to university While there may be broad support in principle for equity in tertiary institutions, there are many serious issues simmering below the populist mantras being espoused by vice-chancellors eager to be the best boy in Julia Gillard's class (''Cracking open the academy'', April 3-4).

First, not all students aspire to a tertiary education, nor should they, even those who may be judged the ''best and brightest''. We need a diverse workforce, including in trades and technical and paraprofessional occupations that do not require tertiary qualifications. Second, the regional universities were established to cater to regional students, who often experience financial and social stress when moving to large cities to study. What is the rationale for the Go8 universities to poach the best regional students? Third, the attrition rate of students from lower socio-economic background from universities is significantly higher than the average. In smaller and regional universities it is higher still, up to 35 per cent in some centres. One reason is the low ATARs under which these students are admitted to tertiary institutions. Another is the lack of support once they are enrolled. All students need to be encouraged to reach their potential. Let's not set up significant numbers of students for failure just to meet the latest political agenda.

We should be directing our attention to children from disadvantaged backgrounds, and ensuring that the origins of disadvantage are addressed at their source, rather than offering these young people five-point bonuses on the ATAR at the end of their education. Dianna Kenny Professor of Psychology and Music, University of Sydney We are told that the My School website introduces a stigma for schools and pupils. The proposal by universities to give preference to disadvantaged students primarily on the basis of the schools they have attended also raises a stigma for the school, the teachers and the pupils. The concept of disadvantage is subjective and many experience significant disadvantage that

is neither recognised nor acknowledged. At least the assessment based on the HSC is objective, fair and open. Michael Sobb Rydalmere Farmer at the helm will set you straight I am a simple farmer, unable to steer modern, large farming equipment to a desirable degree of accuracy. Fortunately, for a small outlay (about $20,000), satellite technology is available that will guide the machine to an accuracy of two centimetres. Turns and corners are easy. The operator simply watches. Most farms use it. Why, then, might ships near the Barrier Reef, or anywhere else, need a pilot (''Shipping crackdown urged to protect reef from disaster'', April 5)? Why not an accurate chart, autosteer and a couple of farmers to install it? The Shen Neng was 15 kilometres off course - if we were that bad we would be on another farm.

Ross Flanery Galong Perhaps the captain and crew of the Chinese coal ship should be arrested and tried in secret for crimes against the state. Don Leayr Albury Don't belittle abuse The Catholic Archbishop of Dublin finds the Archbishop of Canterbury's assessment of the devastating effect of the sex scandal on the Irish church ''unhelpful and undeserved'' (''Easter messages turn on Catholic Church's crimes'', April 5).

No wonder the church's response to victims of abuse has been to trivialise their experiences and attempt to silence them, while moving the perpetrators to new pastures and denying knowledge of their activities, to protect the ''good name'' of the church. Jennie Morris Wollongong Stimulation makes economy weaker Richard Davey (Letters, April 5) is correct that fiscal policy is not needed to stimulate an economy except in a Keynesian liquidity trap, conditions that did not exist in Australia. Also, the form of the stimulus used here - extra government spending rather than tax cuts - has further bloated the command economy and increased monopolies, while weakening the market sector. The inefficiencies in resource allocation this has caused will waste billions more dollars in the years to come. None of our politicians seems to get this, but the economists in the Treasury should.

Peter Carroll Glebe Climate stupidity a lasting monument It would be wonderful if commentators such as Chris Berg lived to see the consequences of their bone-headed thinking (''Face facts and adapt to a warmer world'', April 5). His column should be placed in a time capsule and his descendants made to wear a copy around their necks for 500 years. His assertion that man-made constructs (such as economic growth) will triumph over a ticked-off Mother Nature shows hubris at its worst. Has he any idea of the forces that would be unleashed by a 2- to 6-degree rise in temperature? People alive in 300 years will be floored at our stupidity and ignorance of many things, one of the stand-outs being our frittering away of the precious time given to us to reduce carbon emissions. I am indeed feeling glum. I learnt of the dangers of global warming due to the burning of coal and oil at university 40 years ago. Jim Lavis Raglan

Protectionists clearly have Kindle in their sights Louise Adler's rant about the Kindle and like devices exemplifies the negative and protectionist attitude of so many book publishers (''Spirit of literature turns to Kindling'', April 3-4). It was an attitude we saw in full force in last year's debate over parallel import restrictions, in which Ms Adler was a keen advocate for their maintenance. This we-know-what's-best attitude towards readers has driven many of us online, where we can find books more readily and cheaply, arriving with less delay and now, in some cases, free of postage costs. Ms Adler seems to attribute to the Kindle all manner of sins. Apparently it will lead to self-publishing, bland internationalism, mass-market titles and more such horrors. It may come as a surprise to her, but readers are quite capable of working out the uses and limits of an e-book reader. She may be happy to travel with the added weight of several books in her luggage, but many of us are not. An e-reader deals with that problem nicely, and with that of the other papers many of us carry. Ms Adler fears we will be lost in some e-book wilderness when we discover that not all titles are available in that form. I can't always buy certain foods fresh, but I have managed to work out that I can probably buy them in frozen or dried form. We might be able to apply the same skills to book buying as we do to so many other purchases.

There may be concerns among authors about the impact of e-publishing. The English author Lindsey Davis explains why she has resisted e-book versions of her Falco series, but in a way that does not condemn the e-book industry or reader. I am looking forward to the arrival of my Kindle, just as I will continue to look forward to my next wander through one of my favourite bookshops. I might even buy a book or two. Lesley Hitchens Randwick Farm animals not shown in true light

Is it not a little disingenuous to exhibit farm animals at the Easter Show as cuddly, young, fluffy and cute, when the show animals are as far from typically farmed animals as it is possible to be? The mother pig and piglets have space to suckle and play but in reality the vast majority of pigs are factory-farmed in inhumane conditions, often using sow stalls - oddly not shown at the show.

The Easter Show is intended to show children what farm animals look like, but doesn't show the rest of the story. We need to present the real story of where our food comes from so that we can make informed decisions to drive our shopping habits. We should not hide the truth from children, nor deny it to ourselves. To do so is to perpetuate the disconnect between the image of the fluffy, cute lamb and that tempting wrapped package in the supermarket. Judy Hungerford Crows Nest Track him down As I enjoy the safety of this land (and have done since the age of 13 in 1974) I trust the Australian justice system will track down and extradite Dragan Vasiljkovic (''A search for justice'', April 3-4). How anyone who knows the story could hide this fugitive is beyond me. Whatever happens to him, he will have the opportunity to defend himself, an opportunity denied men and women from my home town of Zvornik. My memory of my birthplace, a town where Muslim, Orthodox and Catholic lived alongside one another without a bad word, has forever been erased. May Vasiljkovic find justice.

Fadil Pedic West Pennant Hills Reduce the brakes It is not only Paterson that has to suffer the infrastructure and environmental damage caused by RailCorp's Martins Creek quarry trucking operations (''Community carries burden as RailCorp keeps on trucking, says mayor'', April 5). The small towns of Bolwarra, Bolwarra Heights and Lorn are also suffering, yet Maitland City Council appears oblivious to the impact of these trucks. A letter to the council requesting that a sign be erected asking truckies to reduce the use of compression brakes was met with silence. I assume that since the trucks are not in councillors' backyards at 5am, it is not an issue. Keith Pearson Bolwarra Can't stop progress

Moya Ward (Letters, April 5) is right about the Kindle. I have ordered one and am waiting with bated breath until it arrives. Many people are affronted by the cost of books and environmental destruction that occurs to produce hard copy. The future will be electronic books. We are witnessing a transformation of monumental proportions. Luddites such as Louise Adler are standing in front of a powerful locomotive of change (''Spirit of literature turns to Kindling'', April 3-4). Raymond Seidler Kings Cross Better than nothing The emissions trading scheme wasn't very good, but at least it was a start, and better than anything the Liberals were suggesting. Now that I know the Nationals were behind moves to kill it, I can confidently place them last on the ballot paper at the next election (''ETS fight inspires ad'', April 5). David Neilson Invergowrie

No minister For goodness sake, David Tierney (Letters, April 5), why would you conjure up a Minister for Copulation? How long do you think it will be before the government takes that on board? And what of the junkets - when three-quarters of the cabinet gallop off overseas on a "fact-finding mission"? A bit more thought in future, please. Dan Sutherland Clarendon Serious fun How much fun can you get from one article (''Gentlemen, play by the rules: it's one stripe or none'', April 5)? I have a feeling Ross Cameron was dead serious, but he made my Monday.

Megan Heaney Kincumber