He is close to saying ''Don't blame alcohol so much for the violence. Blame social media and upbringing, etc.

Has Mr Jack ever been inebriated or dead drunk? If not, then he cannot appreciate the power of alcohol as a drug, whose effects on the drinker will be uniquely determined by his/her physiology, psychology and circumstances.

It is natural for adolescents to seek emotional release from the rigours of parental and school discipline.

Unless one has experienced the liberating effects of inebriation, when young, one hasn't really lived. Unfortunately the tipping point into drunkenness and disorder can be totally unpredictable in timing and consequences. From experience and observation I have found that young people from families in which alcohol in moderation is just part of everyday living appear to meet fewer problems during the often turbulent years of adolescence.

Where family discipline has been tight and lacking in the intimacy of good relationship, the energy released by alcohol in adolescence may be intensely liberating. In the martial arts, cultivating a strong ethical discipline should be mandatory.

The wisest approach is to follow Socrates: ''know thyself''. Take it easy.

Ralph Sedgley, O'Connor

Vic Adams (Letters, January 9) made a number of false claims about my views on service pensions and the Department of Veterans Affairs. An email doing the rounds in the veterans' community involves a concocted quote purportedly from me about abolishing the department and reducing service pensions. Another email says I plan to introduce a private members bill to do this.

These claims are wrong, outrageous and are a reprehensible attempt to besmirch my reputation. It has never been my view or the views of any organisation I have worked at to implement these policies.

I note that there was an attempt during the election campaign to try and fit me up with these claims.

The political games continue. Clearly this is an orchestrated campaign. But to create anxiety in the veterans' community in this way is a low act. All I ask is that the Coalition is judged at the end of this term by what it has delivered for veterans.

Dr Peter Hendy MP, Member for Eden-Monaro

Jack Waterford is described as editor at large. After reading his article in The Canberra Times of January 8 regarding the next governor-general, I think he should be recaptured and put back on his medication.

I can't remember why I stopped reading his articles some time ago, but with a little extra time on my hands the other day I stumbled across his recent attempt to denigrate Peter Cosgrove. Now I think I know why I don't normally read his articles.

To suggest that the governor-general needs to be a lawyer is laughable. In the unlikely event that the G-G encounters a constitutional crisis within their limited time in office he/she would have at their disposal all the resources of the legal brains of the country to draw from. What would be required is someone with the nous to draw on this knowledge and make the best decision for the country. It would be better if the person did not rely on their own knowledge of this specialised field of law and was not carrying baggage of the past or pushing personal legal agendas.

In his argument to suggest that the G-G needs to be a lawyer Waterford resorts to the actions of King James II of England in 1680 (surely the job has changed a little from that time). He barely mentions a more recent example where a controversial decision was made (and if my memory serves me correctly the person involved was a lawyer).

Waterford says that ''many of his colleagues … think he was promoted past his abilities, etc''. Who are these colleagues? What were their motives for passing on these opinions?

It is hard to think of a person better qualified and more suitable to do the job, such as it is, than Peter Cosgrove.

Why Waterford has set out, using spurious arguments to suggest he is not capable is curious. He may be more clever than me at cobbling some words together to promote a cause, but I know shit from clay.

Jim Castrission, Campbell

Why the dithering on new governor-general nominations? Marlena Jeffery is female, has the military connection, some experience on the job, speaks well and has some sex appeal for Tony.

Michael Duffy, Curtin

What a delightful story on young Sophie Lester, CSIRO, dragons and a future career in science (Times, p1, January 9).

I can only hope that by the time Sophie is old enough to have launched her science career that she will enjoy a more appreciative public view of her profession.

Prime Minister Abbott's men, Maurice and Campbell, as well as sharing the surname Newman, seem quite at ease in vilifying scientists in general and in particular those who through rigorous research and modelling believe that climate change is being accelerated by human activity.

Our family was immensely proud, late last year, to attend the conferring of a PhD on our daughter for her study on the potential effects of climate change on areas of horticulture. She was also selected to deliver the valedictory address and she urged graduands to their responsibilities on what they could give back to the country now that they had completed their studies. What an insult to her dedication, integrity, hard work and scholarship that her area of science should be so denigrated by the likes of the Newman duo.

Ann Darbyshire, Gunning

Gwynne Dyer's article ''Supervolcanoes ready to rumble at any time'' (Times2, January 9, p5) gives some idea of the potential danger of ''supervolcano'' eruptions, but tells only part of the story.

The first point to make is that we don't always ''know where they are''. In February 1943, a small hill appeared in a cornfield near the town of Paricutin, Mexico. It had a fissure about two metres wide and nearly 50 metres long on top of it. Within a few years, Paricutin was a conical volcano 424 metres high, sending fine ash 200 kilometres to Mexico City and covering 26 square kilometres of farmland with lava and coarse ash.

Even closer to home than Toba, Sumatra, is the Taupo supervolcano on the north island of New Zealand. The Taupo eruption, about 1800 years ago, sent volcanic debris 50 kilometres into the air, covered all of New Zealand with fine ash, covered everything within 90 kilometres (except Ruapehu) with up to 100 metres of hot (500+°C) pyroclastic flow material, and may have caused the red sunsets reported at the time by the Chinese and even the Romans. Taupo is classed as dormant, but not extinct. The Yellowstone supervolcano is also far from extinct.

Huge, and hugely destructive supervolcano eruptions are not rare in geological time, and could happen again at almost any time. However, armed with modern technology and knowledge, we can say that this will probably not happen in the next few decades, and that we should have a few days - maybe even weeks - warning when it does.

Dr Douglas Mackenzie, Deakin

Professor Frank Zumbo writes in his article (''Air-rail links not pie in sky'', Times2, p1, January 7) that there should be, in fairly short order, a second Sydney airport at Badgerys Creek, and a high-speed railway link, for passengers and freight, between airports in Melbourne, Canberra, Sydney (including Badgerys Creek) and Brisbane. This would lead to, inter alia, a faster and more efficient freight movement system.

Unfortunately, a high-speed passenger rail system such as has been proposed in various forms for the past 25-plus years cannot be used by freight trains, principally because freight trains cannot operate at high speed. Even with today's technology and advanced control systems the top speed of a freight train is limited to about 100-110 km/h - and most trains would rarely reach that. True, as was advanced in support of high-speed passenger trains, some carriages (or even whole trainsets) could be modified slightly to carry some kinds of freight (eg time-sensitive documents, small parcels, specialist limited-life, high-value produce), but wheat, containers, steel products etc are out of the question. It should not have escaped Professor Zumbo's attention that the Australian Rail Transport Corporation has recently completed construction of an ''avoiding line'' between Hornsby and Campbelltown - to allow freight trains to pass through Sydney at any time, without causing problems for the (very busy) suburban system. Similar but smaller-scale works are being executed in Adelaide, for the same reason.

If a high-speed passenger rail system were built as suggested by Professor Zumbo, then the mode of passenger transport which would suffer most (in terms of decline in traffic) would be domestic air transport - it might well be the case that the reduction at Sydney (Kingsford-Smith) would be sufficient to obviate the need for a second Sydney airport (at Badgerys Creek or elsewhere) for several decades.

So, a ''no-brainer'' solution might require a brain after all.

Paul E. Bowler, Holder

What a pleasure it was to watch those two fine sportsmen Federer and Tsonga play an exhibition tennis match in Melbourne. I was once again struck by the courteous behaviour of both stars. This cannot be said of some other players who carry on with the most peculiar antics.

Cynthia Moloney, Yarralumla

ARTIFICIAL GREEN?

Regarding Kingston's Green Square, would artificial grass be a good idea in view of possible droughts and high water costs?

Colleen Perriman, Page

MULTICULTURAL POINT

How can anyone argue Australia is not a multicultural nation when our up-and-coming junior tennis players are Bernard Tomic, Marinko Matosevic, Nick Kyrgios and Thanasi Kokkinakis?

C.J. Johnston, Duffy

PAPAL BRAINWASHING

S. Engstrom, Jan Gulliver and Barrie Smillie (letters, January 7) are despairing of the ignorance of Cory Bernardi. But it's just another manifestation of the brainwashing exhibited by so many followers of Il Papa, our current PM included.

T.J. Marks, Holt

BLIND FAITH

''Strap on this explosive vest, little sister of 10. Here now, go into that crowded place and blow yourself up, along with much destruction, many dead and many maimed for life.'' ''Thank you, brother.'' ''Then, little sister, you will go straight to paradise.'' Ah, the blessings of a faith in god.

Ned Ovolny, Duffy

JUMPIN' JACK GAS

With the media reporting that 2013 was the hottest year on record, I checked 2013's gas consumption against 2012's. In 2012, I used 144 megajoules and in 2013 I used 230 megajoules. Thank god it's getting warmer.

Bill Dobell, Sebastopol, Vic

HEARTBREAKING JOB

The navy is trained to defend the nation against bad guys with guns who mean us harm. I wonder how sailors feel about being given the task of pushing unarmed, frightened people, fleeing death and danger, back out to sea?

Digby Habel, Cook