Professor Michelle Sovinsky, of the University of Zurich, talked about a model she and a colleague have devised for answering, with the facts (all entered into complex and searching algebraic equations), some of the controversies that come up whenever both sides are arguing passionately for or passionately against the legalisation for marijuana.

She says theirs is "the first approach to modelling and estimating the impact of legalisation (of marijuana) on use (of marijuana)".

Her audience in the seminar room (we wish we could report colourfully that it was one of those famous "smoke-filled rooms" but it wasn't) seemed, from its informed questions and observations, very marijuana-literate. It reminded me yet again of what a sheltered life I lead. Words like "head" and "hydro" and "leaf" were knowledgably bandied about.

The professor makes the point that legalisation of marijuana use and decriminalisation of its use are not the same thing.

In the ACT we enjoy decriminalisation (that is we will not be thought criminals if we are found to have some small amounts for our own use). But it is only in eccentric Uruguay where as well as use the production and sale of marijuana is legal too, albeit with guidelines. Even in the notoriously liberal Netherlands, where marijuana is often sold where coffee is sold, consumption is tolerated while the law continues to frown on those who supply it to those so free to use it.

In Uruguay's special case there has been such alarm at the way the young make use of other notoriously hard and life-ruining drugs that there is some hope that weaning them on to marijuana will do them less harm.

But in very Catholic Uruguay the policy is controversial and the anti-legalisation folk invoke all the arguments (like the idea that the marijuana-indulged young will move through the "gateway" of marijuana and on to worse things) that the professor and her colleague say that they can forensically test for truth and likelihood.

Their scholarly paper bristles with startling statistics. For example, they calculate that there might be "a 67 per cent post-legalisation increase in the probability of teenage use".

And yet "it is likely that underage users would face the same (if not even more harsh) restrictions as they face for alcohol use, which is illegal for those aged under 18".

There was some entertaining discussion about how, with the sale of marijuana made legal, those selling it might resort to advertising their product vis-a-vis its competitors. Someone imagined a grower and seller bragging that his product was "organically grown" and so was desirably "green".

We were haunted by the thought that, however intellectually exquisite the scholars' perfect forumale (you should see them, these masterpieces of creative algebra!) the political parties and governments that form policies on these sorts of things are never likely to worry their heads with objective truths.

Politicians in democracies must abide by what will and what won't provoke opportunistic oppositions and the irrational, sheep-like, shock-jock-shepherded masses.

Knowing and caring nothing of "leaf" and "head" and "hydro" we ambled back to the car across the idyllic campus. It was a flawless Canberra winter day. Young student lovers walked hand in hand and Sullivans Creek, where we crossed it on fairytale, stepping stones, babbled musically along on its way down to the lake. All of this gave us a natural high.

In this witty and playful work by Amelia Zaraftis, the Soft Edges of a place on the Monaro Highway have been made newly, especially soft by there being a vulnerable, soft, breakable human being on the edge.

It is the artist herself, standing beside a soft, cloth version of the usually hard, metallic sign.

Soft Edges and some other works "in which I'm playfully misreading the text of roadside signs [often] on remote highways" are part of the #Sculpture exhibition that opens today in the ANU School of Art's Foyer Gallery. Zaraftis has done a whole semi-playful series, for her Honours thesis, about road travel, its joys and its dangers.

In this case, Zaraftis fancies that she was thinking of how when we are on long car journeys we may be loving "all the freedom and escape" while sometimes thinking of how vulnerable we are as we hurtle down the highway".

"So I was thinking, noticing the Soft Edges signs [that we see from moving cars], of the soft edges of people in cars."

She posed on the verge of the Monaro Highway somewhere between Cooma and Nimmitabel.

This columnist never takes that road (and I take it several times a year going to and from our favourite idyllic far south coast seaside resort at Pornography Point)* without noticing the voluptuous smoothness of the landscape. And this always reminds, in turn, of how indigenous people told the first explorers that this was the Monaro and that the word meant the curvaceousness of women's bodies.

This is why the common, bogan mispronouncement of the word (it should be pronounced mon-air-uh) as mon-are-roe (that's the car) causes some of us such pain. The true pronunciation has such truth and antiquity about it. Promise me, readers, you will always leap to correct those, especially those in the media, who use the vulgar pronunciation.

* Not it's real name.