It never pays to make a case on a pretext. That is why the Government has come to grief momentarily on the Crafar farms sale, and why it is struggling in another argument this week - the "Monday-ising" of our most sacred days.
The reason the Government wants to let a Chinese entrepreneur buy the Crafar farms is that it is really a New Zealand investment in China.
Zhaobai Jiang is offering more than Sir Michael Fay says the farms are worth and the Chinese property magnate might need to recover his stake by putting New Zealand's name on a retail brand in that burgeoning market.
He says he will. He might. He has supermarket connections. If he does put our name up there it would be worth the "loss" of a little arable land.
The Government made this point but in the end it had to pretend Chinese money is going to do something marvellous for the farms, because the report it received from the Overseas Investment Office exaggerated the domestic benefits and doubted the applicant was in a position to do much for New Zealand in China.
Domestically, Zhaobai Jiang is planning to do no more than bring the run-down farms back to full production, which any buyer would do. That was evident to any reader of the OIO report and to the High Court judge who knocked back the sale this week. When the office revises its report and recommends approval for the right reason, the ministers can sign it off. It never pays to make a case on a pretext.
I hope that lesson will be applied now to a subject much closer to my heart.
When Norman Kirk instituted a public holiday on Waitangi Day it was expressly directed that it not be "Monday-ised". Like Anzac Day, but unlike other public holidays, it would always mark the precise anniversary. When the date fell on a weekend, tough.
Well, not that tough. Last year, both Anzac and Waitangi holidays disappeared into weekends and I don't think the stress levels of the workforce rose appreciably. But the Labour Party has drafted a bill to give us the Monday off in future. It might succeed.
National is struggling to find a good reason to oppose it. The Prime Minister took refuge this week in advice from the Department of Labour that the economy would lose $200 million for each day off.
Since we lose this amount in five years out of seven already, and it will be 2021 before both holidays fall on a weekend again, I don't think that pretext can carry the day. This is not an economic issue, it is a sentimental one.
The real objection to the Monday-ising of Waitangi and Anzac days was expressed by Gerry Brownlee on his way to National's caucus discussion on Tuesday. "You would cheapen the remembrance," he said. Exactly.
Dates matter. I don't know why, but they do. My late mother-in-law celebrated 89 birthdays as best she could on December 25. She was always a little miffed at the competition but never tried to shift the observance of her birth, even by a day or two. Nobody would change their birthday - dates are a truth in time. It is only on April 25 that we can say it was on this day the Anzacs went ashore. The morning in New Zealand could have been exactly like this when young men from here were running into hell on the other side of the world.
Every February 6 at Waitangi you can hear the cicadas as Hobson must have heard them when he walked up to Busby's lawn. The trouble with sentiment is it doesn't win political arguments unless the sentiment is universally shared. When it faces rational opposition, it wilts.
It is perfectly rational to say, as Labour does, that a Monday holiday would not prevent anyone observing the anniversaries. The usual ceremonies could be held on the Saturday or Sunday.
Well, if they must be rational about it, why not Monday-ise the holidays completely, like Queen's Birthday, Labour Day and the provincial anniversaries? They always give us a long weekend.
If we are not going to be ruled by sentiment we could reduce the national day to nothing more than a holiday - nothing more significant than Auckland's anniversary day. Who in Auckland knows what event inspired that one?
Norman Kirk understood that a public holiday betrays its purpose if it is detached from the date it commemorates. He was a sentimental man.
If John Key makes that argument against this bill he might marshall the numbers to defeat it. Surely Maori will vote to keep the integrity of Waitangi Day and John Banks would do the same for Anzac Day. It matters.