"Over the years I have felt more guilty about identity theft, and it can't be very original taking on a historical character's name."
However the name worked, he admits, so it's not a brand he wants to abandon entirely - "I'm pretty proud of most of the 350 songs I've recorded, engineered and produced, and the 28 members of the band I've played with over the years". But he would like "to sail into the sunset tentatively hoisting the flag that says 'Ian Anderson' on the masthead. Just so you know I was the guy playing the flute, it wasn't Jethro or Mr Tull".
Jethro Tull sprang to immediate attention in the last years of the 60s when their blend of hard rock, pastoral folk-rock, a smattering of jazz and their increasingly ambitious albums seduced serious rock writers and audiences alike. They became an enormously popular live act for Anderson's idiosyncratic appearance (codpieces weren't that common) and stage energy.
By the early 70s Tull were making massive selling albums like Aqualung (1971) and especially their cornerstone Thick as a Brick (1972) on which one integrated song-piece occupied both sides of the record. At a time of bloated concept albums Brick was serious listening, but also poked at the genre.
Anderson says it was "a conscious attempt to deliver parody and surreal British humour" because of the conceit the lyrics were written by eight-year old Gerald Bostock. The newspaper-style cover was full of in-jokes, the whole album an extension of the British love of absurdity in comedies such as The Goon Show and Monty Python's Flying Circus. Although most beard-stroking prog listeners didn't get the connection.
"Thick as a Brick was intended to work in that area of parody. And set in that excessive, apparently self-indulgent prog-rock scenario, it seemed fitting," says Anderson, a volubly unstoppable man for whom an interview allows a monologue from a pulpit.
"But behind it all lies something serious, which is the mixed and often confusing messages children receive -- that I as a child received in the post-war years, pre-puberty -- where the fictional heroes, the characters we were taught to believe in, and the adult world we thought we were beginning to understand, was distorted through fairytales told by parents, perhaps by an early version of religion and the slightly politically incorrect comic books which would refer to the recent war and our opponents 'Jerry' or 'The Hun'.
"This was the world I grew up in and when I went to Germany for the first time to play I was thinking, 'These were the people we'd been engaged in mutual murder with just a few years previous'. Here I am in Berlin, seeing the ruins of some of that awfulness of the Allied carpet bombing of German cities ... I wanted to talk about that as it affected me as a child, and people growing up in the 60s and 70s too.
"So Thick as a Brick was about the confusion of the pre-pubescent mind."
In 2012, under his own name, Anderson released Thick as a Brick 2 which presented five different scenarios for what had happened to the boy Bostock 40 years on. It was a metaphysical exploration of the notion of Fate, an idea he dismisses.
"I started to write down possible scenarios ... [exploring] the idea that somewhere along the way, things may happen that may push you in one direction as opposed to another, sometimes it's a willing choice. Sometimes you are confronted with a decision-making time where you consciously say, 'I think I'm going to do the double maths, physics and chemistry studies rather than Greek, Latin and Art'.
"There are some clearcut moments where you are called upon to make tough decisions."
Anderson -- who says the New Zealand concerts will feature "Thick as Brick as it was written and recorded in 1972, then some things from Thick as a Brick 2, and the second half is broadly speaking the best of Jethro Tull" with some material from his most recent Anderson-attributed album Homo Erraticus -- had one such moment.
"It was just that, whether to do arts or sciences. I was pushed more towards the sciences because my physics teacher was chummy with my parents, whereas I was much more of a girly flute player in the making ... although I didn't know it at the time."
Who: Ian Anderson of Jethro Tull
Where: St James Theatre, Wellington, December 19; Civic Theatre, Auckland, December 20
- TimeOut