"I am an active pacifist. Of course. Of course," Jan Morice told us on Tuesday, speaking (forcefully) from Sydney, but somehow by force of personality managing to be with us here in a newsroom in Fyshwick.

The author and teacher is an active pacifist about to give a talk at the Canberra Museum and Gallery (CMAG) about her grandmother Mabel Drummond, one of the most active pacifists in our nation's history.

Morice's talk is called The Pacifist and the Soldier and coincides with CMAG's current Women's Power to Stop War exhibition.

The pacifist of the saga is Mabel Drummond and the soldier is Mabel Drummond's brother Tom Gardner (he is the soldier on the left in our photograph). By the time Tom, 33, a miner, leapt to enlist in September in 1914 (he was among the first to enlist) Mabel was a committed pacifist, a founding member of the Womens International League For Peace and Freedom. Now here was her brother, caught up in the patriotic fervour, volunteering to take part in war, for her the most ferocious of human follies.

Morice's talk will follow the tense but affectionate relationship brother and sister maintained from his enlistment and then (by correspondence) during the Great War. Tom's other sisters, and his mother, all supported his khaki decision. Morice says there were countless heated family arguments over the didactic Mabel's refusal to comply with the mood of the times.

We can be sure, Morice says, that in the months between Tom's enlistment and his sailing away that Mabel tried to talk him out of it. We know she made sisterly visits to him at Broadmeadows. She gave him to take with him the present of a book of Shakespearean quotations (a quote for each day of the year) that after the war was found to be well-thumbed and much marked in purple with the indelible pencil issued to soldiers. Perhaps he referred to it often while on Gallipoli.

Morice says that Tom's letters to his sister (beginning with those sent during the voyage and then from Egypt) are at first optimistic and have that boyish "We're off to see Egypt! The war will be over by Christmas," naivety. Then, inevitably, as he began to experience terrible things, his correspondence changed.

From Gallipoli he wrote "Well Mabel, I wish this war was over ... Every one of the occupants of the tent you visited us in at Broadmeadows are all wounded, and the fellow whose mother used to come and visit him there has been killed."

Meanwhile back in Australia Mabel Drummond was of course a warrior with the anti-conscription forces in the bitter conscription referendum campaigns of 1916 and 1917. She spoke at mass-attended turbulent rallies.

A now embittered and sarcastic Tom (now serving in France) wrote to Mabel about the conscription imbroglios, saying he knew of thousands of his colleagues who voted a resounding "NO" to conscription. And yet "It will be such a pity if the boys stop home and lower the revenue by accepting the old age pension, when they can come out here and get buried for nothing. I think the undertakers in Australia must be exerting their influence [at the referendums] to induce them to stay."

Morice says that Tom was in despair by 1918. He wrote, "Curse the army for keeping me here and bringing troubles on poor innocent women [his mother was ill] who have to stay home and fret their hearts out, although it was my fault for being such a fool to enlist."

Later that year he writes "my nerves are rotten now ... I am so nervy I cannot bother about anything."'

He was discharged in October 1918, suffering from "shell-shock" that of course, Morice says, we now know to be Post Traumatic Stress Disorder (PTSD). Home in Victoria he drowned in November 1918. He'd had a massive heart attack while swimming. He had been badly enfeebled by his war service, hospitalised twice with rheumatic fever while serving in France.

Morice's side of her conversation with me was very passionately delivered (her talk is set fair to be similarly heartfelt). Her feelings are all bound up with fondness for the grandmother she knew well ("I loved her. She was so strong!") and with her conviction that the men now coming home from Afghanistan and Iraq, with PTSD, are our latest Thomas Gardners, victims of the same old ferocious folly.

"There is an absolute parallel. Just like him they've been horrified by what they've seen. The basic human instinct is not to kill another human being [but then war and soldiering require it]. I feel great compassion for them and their wives and children."

She finds politicians' and others' jingoistic and sentimental sentiments (due to increase in volume as Anzac Day looms) about there being glory in war "just grotesque". The Great War's pacifists will get few if any guernseys in the Anzac speeches of our potentates, but she, Morice, will raise her contrary voice in The Pacifist and the Soldier.

Mabel Drummond's pacifist convictions never wavered. She was president of the Women's League for Peace and Freedom during WWII. She died in March 1968, almost 91 years old.

"When I knew my grandmother," Morice reminisces, "she was a dignified elderly lady, her eyes piercingly blue, her voice still ringing with the cadences of a public speaker."

The free talk The Pacifist and the Soldier is at CMAG at 1pm this Friday.