Why not waste your vote? A general election is at hand, and the cry of the tactical voter will be heard before the first cuckoo. He will tell you, with a knowing air, that you must not waste your vote and how not to waste it, and it is important not to believe him.
Any vote is wasted, the tactician will say, that is not decisively cast for a winning candidate. But to make that true, the winner's majority would have to be as slim as one or two votes, and apart from Winchester in 1997 it is hard to think of any parliamentary seat in our times that has been decided by a margin as tiny as that (even then, the High Court ordered a recount due to the number of void ballots after the ousted MP complained).
To allow that possibility to govern your choice is wildly absurd, and anyone can see it. To suppose you can predict where it will happen is wilder still.
Put this to the tactician and he will switch off his knowing look and explain that he hopes to mobilise others to vote the same way. In that case, he may make a difference. But he may equally make a difference by persuading people to vote for a candidate on grounds other than tactical ones, so the case for tactical voting is still a nonsense.
However it is learned nonsense. Four centuries ago, Michel de Montaigne called that sort of thing "doctoral ignorance", implying that you would need a PhD to believe anything so silly.
More recently another Frenchman, the late Raymond Aron, stigmatised Marxism as The Opium of the Intellectuals (1955), a drug for the educated. That was half a century ago, in Soviet times, and it all came tumbling down with the Berlin Wall in 1989.
But it remains the classic instance of intellectual self-delusion in our times, and the myth of tactical voting is a mere trifle in comparison. Like communism, it is a drug for intellectuals, a prime case of doctoral ignorance. Ordinary people know better. They vote out of habitual loyalty, often enough, or a sudden preference born out of television news or newspaper headlines. Democracy means that the people know what they want, as H.L. Mencken said, and should get it good and hard.
If no single vote will affect the composition of the next House of Commons, why bother to vote at all? There are two good reasons, and I suspect that both would have impressed Montaigne, who was not a democrat, and Aron, who was.
The first reason is to fulfil a constitutional duty. Whatever the electoral system, now and to come, the House of Commons is an elected chamber, and in national terms the only one there is.
Five years ago Labour was elected to a third term, with 56 per cent of the seats, on 37 per cent of the votes. There has never in all history been a Labour majority in this country.
In 1945 the Labour vote was 48 per cent, and no British postwar government has ever represented a popular majority. That is a melancholy distinction, since it cannot be said of any other European country.
The "mother of parliaments" is not the model for parliaments, and those who vote as a constitutional duty may have to grit their teeth as they do. But then doing your duty is often like that. There is said to be a Russian proverb that goes: "Better an old hat than a bare head."
The other good reason to vote is to say what you want, whether it makes a difference or not, and we have all had plenty of practice at that. In my years of teaching at universities I became entirely accustomed to it, but it had started a lot earlier. In my cradle, or so I imagine, my burblings were disregarded. At school I was treated as a schoolboy, which in those days meant I was never asked an opinion of anything and was ignored if I ventured to offer one.
As a student I was largely silent, being surrounded by people who were cleverer than I or who thought they were, and my first teaching job, which was in the US, was embarked on with several thousand miles, mostly seawater, between me and home.
In short, I have good reason to treasure the blessed privacy of the voting booth or the postal vote, and plenty of experience of being ignored. As a veteran of impotence, well seasoned in wanting what I cannot have and in surviving disasters I cannot avert, I look forward to Thursday 6 May for the chance to say what I think.
Being naturally opinionated, I find it exceptional even to be asked. It will be a pleasure to answer. What others want is a matter for them. If they choose to vote tactically, the loss is theirs. They are wasting their vote, in the only sense of waste that matters, if they ask for something they do not want.