John Berger, who died on Monday at the age of 90, was the most important writer on art in the last 60 years or more.
There will be those in the academic and art worlds who would reject this judgment.
But in terms of influence on the wider culture globally, it is clearly true.
This is all the more remarkable because he was an intransigent rebel and Marxist.
One of his earliest works, a collection of essays taken from his time as the New Stateman art critic, was called Permanent Red.
The title was a declaration of intent that, “I would never compromise my opposition to bourgeois culture and society.” He stood by his word.
Berger was much more than an art writer. He was a painter, poet, novelist, film writer, playwright, political and social essayist, philosopher and more.
His range was extraordinary.
It went from examining the lives of peasants in the French Alps, among whom he lived for over 30 years, to looking at animals to a dialogue with Zapatista leader Subcommandante Marcos.
This exceptional breadth of knowledge and sensibility made his writing on art so powerful.
However it was on art that he made his major intellectual contribution and for which he will be most remembered.
This brings us to his best known work—the TV series Ways of Seeing and book of the same name, in 1972.
It is hard now to remember or express how revolutionary these were at that time.
Ways of Seeing was, in form and content, completely different from and opposed to the kind of “culture” programmes broadcast by the BBC both before and after.
It advanced, without concessions, a serious Marxist argument about the entire Western art tradition since the Renaissance.
The book did the same and together they represented a challenge to the way in which art was normally understood and presented.
Art history was never the same again.
Berger looked at oil painting from its beginnings in the fifteenth century to the nineteenth century.
His case, in essence, was that it was uniquely adapted to depicting objects and people as things to be owned as private property.
In other words, it was an expression of capitalist social relations.
His argument included a critique of how this systematically depicted women not as active subjects but as objects to be looked at and possessed.
This was particularly revolutionary at the time.
Another hugely important book was his Success and Failure of Picasso (1965).
This explained Picasso’s greatness and recognised how his immense wealth and adulation isolated him and damaged his art.
Berger’s writing was distinguished by its ability to sustain a Marxist critical approach without losing sight of the intense creative human engagement involved in every serious work of art.
And this intense human engagement was a quality that Berger brought to everything he wrote and said,whatever the subject.
I often disagreed with his specific artistic judgements.
But reading anything by Berger involved entering into an intimate relationship with an extraordinarily engaged human being.
His commitment to human emancipation was inscribed in his every word and look.