He's talking about his schooldays at St Bede's College in Manchester, between 1955 and 1963, and about the scores - possibly hundreds - of former pupils, including himself, who were abused by a towering figure of authority there: its rector, Monsignor Thomas Duggan.
Duggan was at the school between 1950 and 1966, and for 16 years abused at will, according to his victims, who are now in their 50s and 60s. Then in 1966 he was suddenly removed from the school and sent to Langho, near Blackburn, in a transfer that was - bizarrely given the nature of his tenure - against the wishes of his parishioners, who were almost entirely in the dark about his attacks on his pupils.
"You wouldn't think of telling your parents," explains Harding, now 66. "They wouldn't have believed it. And then life for the boys who told would have been worse. It's a terrible thing not to be believed."
The diocese recently told a delegation of former pupils that, oddly, there appear to be no extant records about Duggan at all, although Harding believes that he died a couple of years after being removed from St Bede's.
According to Paul Malpas, a businessman based in Ireland who was in the year below Harding at school, Duggan "used to meet boys in the corridors, put his arms around them and rub his face into theirs, whilst asking 'are you being pure boy?'.
"On other more secluded meetings he would put his arms round boys and lean into them, rubbing his face and his body into theirs, groaning and moaning into their ears or sometimes, with the more naive boys, [he would] threaten them with expulsion from the school for nothing in particular, just to put the fear of god into them.
"As a punishment of last resort and this could be for failing a monthly Latin test or some such evil crime, a pupil would be sent up to Duggan. His preferred method of punishment was to tell the pupil to remove his clothing below his waist and stand naked in front of him whilst he spoke to the boy of his poor record. He would then either lean him over the arm of a sofa or put the lad over his knee and wallop him with a strap and at the same time fondling his rear end to presumably make the pupil more pliant."
Harding was one of the (slightly) luckier ones and was never sexually abused. "I don't know why - maybe he didn't fancy me. But I used to get a hammering from him physically. My best friend - who I've known since the age of five and went through school with - was [sexually abused]. I'm so angry about it all."
And with good reason. For although Harding moved on successfully into adult life, forging a career in music and comedy - these days he makes Radio Two's folk show, which is on at 7pm on Wednesdays - he says that the campaign with which he is involved, to get a fulsome apology from the church for what happened at St Bede's, is motivated largely by the knowledge that many of his former classmates' lives were irredeemably blighted by their experiences at Duggan's hands.
"There are two cases that I know of for sure that were terminal," says Harding. "There was one guy who threw himself under a train and another who died in a crack den in Manchester. Both were abused and it marked them for life. I went to university with the one who died of the overdose and we stayed friends afterwards. He would bring up the subject whenever school was mentioned. He messed up his life through alcoholism and then wound up on drugs."
Harding's involvement in the campaign began last year. "I was emailed by a friend in America, who'd been abused himself, about a blog that was being written by Paul Malpas. He'd had former St Bede's pupils writing to him from all over the world, saying that it had happened to them too over years and years."
But recent meetings with representatives from the diocese of Salford, which was directly responsible for the school at the time, have failed to produce a result. You can listen to a recording of the first meeting here.
At that meeting it was admitted that the church had long known what Duggan's time at St Bede's had involved. "Some of the boys who were abused by him had gone into the priesthood and so it was known about. But if these rumours were going around for so long, why was nothing done earlier?" asks Harding. "Father Barry O'Sullivan, who came as a representative of the diocese, said that he'd been waiting for it to come up for years."
Harding says that it's not the campaign group's intention to bring approbrium on the school, which is now an independent grammar that accepts girls and boys, and is no longer entirely run by priests - though there are several on its governing body, including the chairman.
"It's changed beyond all recognition," he says. "What I want is a full apology from the church in the same way that an apology was made for the industrial schools in Ireland."
"All these men have come forward after all these years," says Harding, "because they want the truth out. Many are not young men any more and they want some kind of closure. At the time they each thought they had been singled out because there was some defect in them. But it wasn't their fault and the church owes them an apology.
"What I've seen so far is a statement by the Bishop of Salford [see below] that makes it look as if the abuse is something that was 'reported' and 'alleged'. He's not actually acknowledged that it took place.
"What the church has always done is see this kind of abuse as being in breach of canon law, and dealt with it by moving priests around and putting them in safe houses. But in fact these were criminal acts that took place.
"I lost my religion when I was 14 because of the barbarity of that school, the hypocrisy of the priests - Duggan wasn't the only abuser - and because I had a theological problem with the notion of an omniscient creator who saw it all. I began questioning my faith because of physical abuse at school and it led me to question the whole of Christianity.
"I think what we've heard about so far may turn out to be the tip of an iceberg. If any other former pupils at St Bede's want to add their testimony they can contact Paul on email@example.com."
* This is the text of an apology drafted by the Rt Rev Terence Brain, the Bishop of Salford, and originally intended for publication in the Manchester Evening News. "I am shocked and saddened by the complaints from some former pupils of St Bede’s College which have been brought to the attention of our Safeguarding Commission. The complaints have been made against the late Monsignor Thomas Duggan and relate to the period of time from the 1950s to the mid-1960s, when St Bede’s was a diocesan school. Although it is not suggested that there was a culture of institutional abuse at St Bede’s, nevertheless the abusive behaviour which has been reported has no place within the Catholic Church. I acknowledge and am deeply sorry for the pain and distress reported to have been suffered by those affected."
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