They think highly of Finance Minister Brian Lenihan at the Economic and Social Research Institute (ESRI), the think-tank that offers some of the most rigorous financial analysis in the country.

While Mr Lenihan's late-night visit to David McWilliams and strange habit of chewing garlic has been well documented, the ESRI people are far too discreet to trumpet the minister's two visits in the last year to the docklands headquarters, where he engaged in a debate with a room full of economists. That's two visits more than his predecessor.

This love of debate is one of the things that distinguishes Mr Lenihan from most of his Dail peers. An intellectual who has a better academic career behind him than any other TD, he has been able to swiftly master his brief at one of the most difficult and fast-moving moments in Irish history.

There have been serious blunders along the way, but he has learnt quickly (not least that no one view is right) and the crisis has been the making of him; proving wrong detractors such as Bertie Ahern who disliked his infectious jauntiness and believed he lacked the backbone needed for high office.

The trademark Lenihan bonhomie has rarely left the 50-year-old minister since he took up the post although his aunt and former Enterprise Minister Mary O'Rourke has painted a picture of an almost broken man last September when she met him as he shepherded his controversial bank guarantee bill through the Dail.

"He was three nights without sleep and he was snow white going into the Seanad on Thursday morning," his aunt told the press after she encountered him on his way into the upper chamber. "The sight of him brought the mother out in me."

Mary O'Rourke is one of several family members to have held high office over the years and one of at least three who have been shafted by Fianna Fail, the party they all chose to join and serve in. The others are Brian Lenihan Snr who was famously dismissed from Government by Charlie Haughey, who described him as "his friend of 30 years" before sacking him from Cabinet in the middle of the 1990 presidential campaign. The other is Brian Lenihan himself who was kept out of Cabinet for a decade by Bertie Ahern much to the dismay of many within the party.

So what drives Brian Jnr? Why is he the man to stand up in the Dail on Wednesday to tell us how much we'll have in our pockets next year?

It is tempting to see the sharp and savage end of his father's political ambitions as a driving force. Many other successful politicians have been driven by their father's failure at the highest levels. Psychologists often attribute Winston Churchill's success to his father's abrupt resignation as chancellor of the exchequer, surrounded by the whiff of scandal. Some see a similar motive behind George W Bush's presidential ambitions after his father's unexpected failure to win a second-term following the first Gulf War.

Those who are close to Brian Lenihan believe he is indeed driven by the desire to be Taoiseach. They say he could have been a great lawyer but his mind was always elsewhere, on politics, minding his father's Dublin constituency while the father sought medical help in America and later representing the constituency in his own right. He is certainly not afraid of power: the bill to create the National Asset Management Agency (NAMA) gives the minister powers to make or break the banks that few other politicians would have allowed themselves.

While his father's very public failure at the end of a long career may motivate Lenihan, he was driven before this, since boyhood in Athlone and later, from the age of 12, in Dublin.

He shone as a student, first in Belvedere College, the private Jesuit school where he became head boy, and then in Trinity where he won the most prestigious and practical scholarship in his second year, entitling him to free accommodation, meals and Guinness during his student days.

A Trinity contemporary remembers that Lenihan arrived with his trademark ability and self-confidence ready formed but says those qualities were always mellowed by his courtesy and gentleness. Trinity was followed by Cambridge and a stint lecturing law back in Trinity during the 1980s.

He was too ambitious to remain a lecturer, no matter how congenial he found university life and he was soon practicing as a barrister before standing for the Dail in 1996.

While most of us now think of Lenihan as a finance minister, he had a long apprenticeship on a committee which looked at constitutional reform and as the Family and Children Minister where he recommended lowering the age of consent for teenagers to 16.

Following his appointment as Justice Minister in 2007, Lenihan introduced measures such as a civil partnership bill which went some way to modernising the laws governing the relations between ordinary citizens in this country but showed little inclination to crack down on wrong-doing in the gardai or his own profession -- a problem common to most Irish justice ministers.

It is always difficult to pin down anybody's beliefs, especially perhaps a cabinet minister, but Mr Lenihan's record would suggest that he is a libertarian on social issues but fiscally conservative. While his training as a law lecturer and barrister (and being married to Judge Patricia Ryan, with two children) would have helped prepare him for his posts as Children Minister and Justice Minister, nothing could have prepared him for the job of Finance Minister or the chaos that would come close to destroying the country's banks within months of taking up the post.

Whether you believe Brian Lenihan has done a good job in difficult circumstances ultimately depends on your views on NAMA which means it is probably too early to judge. While Mr Lenihan appears to have done a reasonably skilful job in persuading the European Commission that NAMA is the best option available to Ireland many outside observers regard it and his bank guarantee as a mad gamble.

It was these views that inspired a group of foreign assessors (for the Financial Times) to rank Mr Lenihan as the worst finance minister in the euro-zone last month.

Brian Lenihan knows better than most that reputations can be made or broken in a day. One of those days will be next Wednesday when he presents his fourth Budget in 15 months but the success or otherwise of NAMA will probably determine whether we can recover from the present economic problems and whether he can become Taoiseach more than two decades after his father was denied the presidency.

Irish Independent