But their official titles both overrate and underrate their authority.
Yet this was to underrate Mr Clarke's consistency.Like the jazz saxophonists he reveres, his improvisations and eccentricities have always conformed to a deceptively tight form, in two ways.
World rankings tend to underrate them, partly because non-English-speaking laboratories are penalised.
Political leaders of all stripes tend to underrate Australia's capacity to absorb outsiders.
Or will the big dog simply pad around the White House wagging his tail with nothing but time on his hands?It would be foolish to underrate Mrs Clinton.
But most people outside Japan underrate the power of two ferocious pressure-groups: its doctors and dentists.
Statistics showing Qatar's residents to be the richest in the world, with a GDP per person of $80,000-plus at purchasing-power parity, vastly underrate the wealth of a pampered 250,000 or so who hold the privilege of citizenship.Yet despite the bristling of shiny towers on its waterfront and the freshly acquired treasures in its lavish new Islamic museum, Doha retains a dowdy provincial feel.
Mr Page says Millward Brown has worked more with them than any other firm.Furthermore, he says, do not underrate system two.
A son of the artist and novelist George du Maurier, he won immense popularity, but the fact that he presented characters in terms of his own personality, in contemporary plays, led many to underrate him.
The Qin-Han school tried to underrate the achievements of Han Yu and Liu Zongyuan, along with the Song essayists, and proudly declared that post-Han prose was not worth reading.
The only explanation can be that most men (with the odd honourable exception) consistently underrate the abilities of women.
