He is indeed a writer and lecturer. "I've only done it once before, but I don't mind a bit and I know what's required," he comments good-humouredly, when allowed to relax his pose in the coffee break.
Being an artist's model is not as easy as it looks. You need the ability to remain still and composed for a solid hour or more. And you have to be able to adopt exactly the same pose week-in week-out so that the students can pick up where they left off.
You also need to be completely unselfconscious and in sympathy with the artists. "Good models are like gold dust; it is a tremendously undervalued profession," says tutor JillySzaybo.
In this class the models are always clothed, although in another in the same centre, they are nude. And like the students, they come in all ages and sizes. "Creases and folds are wonderful to paint; they give the subject character," says Szaybo.
Her students tend to be busy professionals - a neurosurgeon, an ambulance driver, a GP, a top civil servant - for whom art is a welcome contrast to their working lives. It's a lively class with plenty of banter. "All day long they've done purposeful things. Here they can let go," says their tutor.
She believes that everyone can paint. "They may not all be satisfied with their work, but everyone is making interesting marks by the end of their first term."
Life drawing "awakens the inner eye" in us all, she says. "People start to notice things and appreciate the world in a new way."
This class takes place at the Hogarth Centre Adult Education Centre, Devonshire Street, Chiswick, London W4. Tel: 0181 995 5934.