Peter Hennessey has been carrying out a fascinating series of interviews on Radio 4 with veteran politicians like John Major and Roy Hattersley.
It is unlikely we will see their like again as the role and make-up of MPs is changing faster than ever before in Parliament's history.
Take Hattersley as an example. A gifted politician who was educated at one of Yorkshire finest grammar schools before they were abolished in the 1970s, he was found a safe seat in Birmingham at a young age.
He never lived in Birmingham, just popping up for the odd surgery. I was active and an office holder in the Birmingham Labour Party in the 1970s and Roy was a remote London figure. His fellow Brummie MPs like Roy Jenkins or Brian Walden were also London based figures. Walden stayed in a hotel when he made his fleeting visits to Birmingham while Jenkins was as remote to Birmingham Labour activists as the Dalai Lama.
Today Labour MPs have to be rooted in their constituency. The first thing Tony Blair, a London lawyer, did on being selected for his north east seat in 1983 was to buy a house there. Weekend after weekend he and his wife would travel up with their children to show a permanent family presence. His wife earned serious money so having a home in both London and his constituency was possible. Today unless an MP is independently wealthy it is not.
The generation of an Attlee, Gaitskell, Wilson, Callaghan or Foot who had safe seats but would never have dreamt of living in them or expecting their families to spend their weekends on crowded roads going to constituencies has been replaced by a generation of MPs whose tweets and interventions at Prime Ministers' Questions are about showing a local presence.
There was a nasty little spat between Austin Mitchell and Stella Creasey on Newsnight after the retiring 79 year old Grimsby MP made some disobliging remarks about all women short lists and the right of constituency parties to chose their preferred candidates.
Austin might recall that the only reason he was chosen for Grimsby after the death of Tony Crosland in 1977 was because he was the local ITV evening news TV presenter and thus a favourite in every sitting room in the town. MPs always have the vanity that they have a special relationship with their constituency and party but if truth be told they are elected because of party labels, nothing more.
But the post-Hattersley Labour MPs have to show much more presence in their constituency than his generation did.
The other big difference is that Roy Hattersley earned serious money writing books and articles which took up an enormous part of his life as an MP. He was a good writer and earned a very handsome crust. This too is impossible for today's MPs. Other than the Murdoch press buying future Tory ministers with a £250k column most newspaper articles by MPs, other than sensationalist allegations or gossip, make little money. The censorious press, social media and parliamentary oversight apparat means that very few of our MPs write, publish, produce major books on contemporary political questions.
To think requires time and training for thinking. And unless you write you don't know if your thoughts matter. The post-Hattersley generation have little time to think or write. They work very hard and are constantly available to constituents and pressure groups but today's MP is constantly on the move between London and constituency, often trying to keep a marriage or family alive as the new hugely expensive parliamentary expenses bureaucracy is family-phobic.
With post-Hattersley generation MPs denied the time to think and write so much more power is handed to civil servants who are sent away to think on secondments, away-days, or taking part in seminars and conferences.
John Bercow is involved in an odd row over plans to import a manager from the Australian senate to be run the Commons. But the real problem is that MPs in the UK sit for more days in London doing nothing very much - the myth of holding government to account is surely one cliché past its use-by date. The Australian federal parliament meets for 72 days a year, half the time of the Commons. The German Bundestag meets for one week a month and Germany is not badly governed.
And if MPs take time off to travel they are traduced as junketeers, The tabloid press and even some of the more stupid rent-a-quote MPs seem to think that if MPs sat 365 days a year the nation would be better governed.
Where Austin Mitchell was right was when he pointed out that the new way post-Hattersley MPs work means more and more MPs are reduced to social worker, or senior councilor status. There are big single issue campaigners like indeed Stella Creasey on pay day loan sharks or Simon Danczuk on dirty old men whose MP status protected them in the past.
But the demands of being a modern MP means it is hard to develop wider perspectives, foreign travel, or ideas from reading and writing. PMQs now never has questions to the PM on international policy. Much of the time the Prime Minister has to answer a protest about why a bus shelter has not been built or accept congratulation from a toady MP that a bus shelter has been built.
Roy Hattersley was never like that. He lived mainly in London, wrote to earn money to supplement the low pay of an MP (compared to other professions), and was not harried and trolled by social media and twitter. Today's MPs, for good or ill, are very different.
Denis MacShane was a Labour MP 1994-201. His Prison Diaries are published this weekSuggest a correction