One of the more interesting aspects of growing older is that you tend to see events rather more in a historical perspective than in an immediate one.
Time changes all perspectives. There are activities we accept as commonplace today which will be considered odious by future generations. Maybe eating meat. Maybe driving cars. Maybe having more than two children.
So if Sean Brady says that attitudes to child sex abuse were different in 1975, he is quite right.
He does not emerge from the Brendan Smyth imbroglio very admirably, but it is still a matter of a fact that attitudes were different in 1975.
And one of the most radical differences was that paedophilia was - at that time - a liberal and Left-wing cause. The trendy, right-on people were campaigning in favour of paedophiles being permitted to express their sexual choices. What today we call 'child abuse' was euphemistically named 'intergenerational relationships' by those who advocated it.
There was a British pro-paedophile lobby called the Paedophile Information Exchange (Pie) and in America, there is still a Man-Boy Love Association.
In the mid-1970s, in the borough of Holborn in central London, the Pie held its own meetings and conferences and in this it was supported by the then National Council for Civil Liberties (now Liberty).
The NCCL at the time - naively, with the benefit of hindsight - regarded Pie as another aspect of sexual liberation. It was argued that paedophiles had sexual feelings like everyone else and any 'liberation' movement should recognise that.
Two women who later rose to the top in British politics were then prominent members of the NCCL - Patricia Hewitt, who was in Gordon Brown's Cabinet, and Harriet Harman, deputy leader of the Labour Party.
The word 'paedophile' was not in general use and neither was the phrase 'child abuse'. Social workers were concerned with incest in the 1900s, when it was known that children could be 'interfered with' by family members.
Among youngsters themselves, there was common lore about 'dirty old men'. But that was all under the official radar: public discourse on the subject was rare. There were no 'paedophile wings' in prisons, as there are today.
Time passed and attitudes changed. Victims of paedophiles began to come forward and paedophilia ceased being a trendy, liberationist cause.
The human rights activist Peter Tatchell still advocates reducing the age of sexual consent to 14. Mr Tatchell maintains that young people of 14 are entitled to a sexual relationship.
Social attitudes were different in 1975 and it is a nice irony that the paedophile liberation movement was then part of the liberal agenda, which now so excoriates those with such tendencies.