On most occasions I would back his judgement of human affairs more than, let us say, Tim Yeo's. But on the subject of contraception and unplanned pregnancy, the Conservative Party contains more experience than the Liberal Democrats can ever hope to equal.
Mr Hughes's latest suggestion, as his party's environment spokesman, is to reduce baby strain on our planet by giving all post-pubescent youngsters the right to family planning advice without their parents' knowledge - so that girls as young as 11 would have easier access to the Pill.
The problem is that it is not lack of the Pill that is the problem. Or, to put in another way, the problem is not going to be solved by giving little girls the responsibility to take a cocktail of hormones. Cheap contraceptives are already easily available, endowed with the remarkable virtue of protection against Aids without any increased risk from blood clots or breast cancer.
But the problem with using condoms lies with the boys.
Mr Hughes would do well to drop green issues for a few days and talk to green boys and girls. Young girls face tremendous pressure not to sleep around. It comes not only from their parents ('Mum'll kill me'), but also from their schoolfriends.
It is quite usual for girls at school to call other girls, who they think are sleeping with boys, 'slags' - and worse. I talked to one pregnant schoolgirl whose family were forced to move house because of the name- shouting outside their home and bricks chucked at their windows.
So why do such girls consent to sexual intercourse; where does the pressure come from? This summer Mizz magazine put the latter question to 830 teenage readers. 'From boys,' said 82 per cent of them.
All the pregnant girls I've talked to became that way for the simplest of reasons: they fell in love. This is an emotion tough enough to deal with at 31, or 41 or 51. Vide Cecil Parkinson. Call Mr Tim Yeo. If David Mellor QC could not act rationally under love's effects, how can anyone 5expect an 11-year-old girl to do so?
Those I've spoken to all fell in love with glamorous older men, aged say, 14, or 16 or 18, with sophisticated lifestyles involving illicit smoking, or even running a car. The girls were bewitched, besotted, their emotions as out of control as those of, say, Alan Clark.
Many were combining their first experience of love's madness with a phase of rebellion against an authority that did not understand: their mothers, schools, the social workers. They were playing truant, running away from home, or just drinking and staying out late. I doubt whether many of them were organised enough to take the Pill, but none wanted to become pregnant. Certainly, without a qualm, they ran the much more fearful risk of Aids.
In their besotted state they were quite incapable of persuading their sophisticated older boyfriends to wear condoms. Some tried. None succeeded. When, inevitably, the girls fell pregnant, the teenage dads overwhelmingly got away scot-free.
The police are not interested - perhaps rightly - in prosecuting young men for under-age sex with girls a few years younger. While the girls are left going through pregnancy and full-time childcare - their schooling endangered, their free time fettered, their parents usually spending supportive time and money - the boys can walk away and wipe all memory of fatherhood from their minds.
The Liberal Democrats would like to see sex education made part of the core curriculum. That would be a start. But emotional education is just as important: how does it feel when you fall in love; how do you say no?
Sex education is not just a question of telling children which contraceptives do what and how babies are born. There is more to it, even, than sending teenage mums to talk to girls about how demanding babies are. If sex education is ever to work, it needs to be wide in scope and aimed much more accurately at the boys' aspirations.
Let us tell the boys from an early age about DNA testing: how fatherhood can be accurately established. Let us explain to the 13- and 14-year- olds the workings of the Child Support Agency; spell out the fact that, as soon as they have a pay packet, something like 30 per cent of it, after housing costs, may disappear until any child they carelessly father is 18, or even older; make them realise what that means in terms of being able to afford a a second-hand Sierra or decent stereo system.
Let us give them a reason not to get a girl pregnant, in terms the most irresponsible of them will understand. Let us propose legislation, even, to place some of the cash burden on the parents of teenage fathers, as it lies at present on most teenage mothers' parents. Let us balance the odds, and not just pass the buck to little girls.