When the old Disraeli, newly created Earl of Beaconsfield, was asked how he found life in the House of Lords, he replied: “I am dead — dead but in the Elysian fields.” These days, though, the place looks more like one of those less alluring parts of the nether world where grey shades are doomed to wander disconsolate, mourning their past lives for the next million years or so.

While the expulsion of the hereditaries may have raised the average IQ, it must also have raised the average age. Gone were those fresh-faced bloods whose father had died prematurely of drink or on the battlefield. While MPs these days all look about 38 years old, most of the peers and peeresses look old enough to be their fathers and mothers.

Yet the Older House was pretty full. When I came in there must have been 100 peers debating “the increasing number of elderly patients who are readmitted to hospital within a month of being discharged” — a subject no doubt of considerable personal interest to many of those present. And when I left there were still at least 50 of them listening intently to an impenetrable statement on European competition policy.

By contrast, over in the Commons there were only a dozen MPs on each side for the debate on the humanitarian crisis in Iraq, a rather more urgent question in most people’s eyes, I would have thought.

The awful truth has to be admitted. Much of the time the shades in Hades not only turn up in greater numbers, both on the floor of the house and especially in their select committees, they also offer more expert scrutiny of the government. And when it comes to opposing, the Lords have more spunk in them than the living dead in the lower house, especially when a government has as big a majority as Tony Blair’s. If, say, 40% or 50% of the peers were elected, that would provide an injection of youth and up-to-date political authority without losing the expertise or threatening the ultimate supremacy of the Commons.

Meanwhile, the Commons has just decided to vote itself family-friendly hours, is fast abolishing the right of backbenchers to be obstructive and now knocks off early for dinner most nights. Which house currently looks more likely to revive parliamentary democracy?

But reviving parliamentary democracy is not Blair’s favourite subject. The prime minister made it clear at question time last week that he wants a compliant second chamber that busies itself with tidying up the bills sent to it and offers no serious competition to the almighty executive — a revising chamber, not a rival chamber. Any Labour MP who opts in Tuesday’s vote to inject even a tiny elected element into the Lords cannot look for early promotion.

“We should be cognisant,” Blair declared, “of the need to make sure that we do not have gridlock and that our constitution works effectively.”

Now when political leaders start using fancy words like “cognisant” and talking about “our constitution”, watch out. As the normally po-faced Austen Chamberlain wisecracked a century ago: “‘Unconstitutional’ is a term applied in politics to the other fellow who does something that you do not like.”

“Gridlock” is the word Americans use when the presidency and one or more houses of Congress are controlled by different parties. In that situation little or no controversial legislation gets through, as happened for nearly a year when President George W Bush lost control of the Senate. But as Professor Murray Weidenbaum, the veteran presidential economic adviser, remarked to me with a quizzical lift of his eyebrow: “Is that so bad?”

If last year’s Queen’s Speech finished in the recycle bin I would not shed a tear. It consisted mostly of futile bureaucratic interventions and misconceived crime bills. In any case conflict between the two houses can often produce fruitful compromise.

Democracy is, after all, meant to be a noisy, argumentative business. Advanced democracies tend to have an elected upper house with considerable powers. Canada is one of the few important exceptions, and its appointed upper house is generally regarded as a dead loss.

In the United States, Australia and Germany, the senate is an important and useful brake on headstrong and half-baked governments and can offer a useful mid-term corrective. If Gerhard Schröder loses the elections in Lower Saxony and Hesse today he will lose control of the Bundesrat and Germany will be that much closer to a general election, which I suspect offers the only answer to her problems.

Blair speaks of a “hybrid” house as though it were a new-fangled monstrosity. Yet as far back as 1910 Lord Curzon, the loftiest of all hereditary aristocrats, was not only demanding the removal of the automatic right of hereditaries to sit in the Lords but also urging the introduction of a mixed house that would represent “the middle classes, the labouring classes and every branch of industry and business”.

Some people like to dismiss these questions as purely theoretical and of interest only to policy wonks. I disagree. Some of the worst mistakes of post-war British governments might well have been avoided if the House of Lords had had the legitimate authority to hold them up and make the government think again.

Hardly any Conservative MPs (in or out of the government) really wanted Margaret Thatcher’s poll tax, but the whips did their stuff. That is just the kind of measure a robust upper house would throw out.

If you have a potent upper house it stretches out the deliberative process. By contrast, if the lower house is allowed to operate as “a battering ram”, to use Dick Crossman’s phrase, the only real thinking takes place before the new measure is even published.

Take top-up fees for university students. A couple of months ago Charles Clarke, the incoming education secretary — a battering ram personified — was “instinctively opposed to them”. Now here he is with a spanking new scheme that he will ram through without MPs having a hope of modifying it.

I hope that Labour MPs on Tuesday, led by Robin Cook, will have the guts to vote in large numbers for a partly elected House of Lords. If Blair and Irvine then defy the democratic will and refuse to embark on any further reform, the House of Lords as it now is will be justified in making full use of its powers and giving the government hell whenever it deserves it.