The French philosopher Jacques Derrida, who died last weekend, is one of the best-known academics in modern times - a controversial figure with the looks of a maturing matinee idol.
But Christopher Norris, distinguished research professor in philosophy at Cardiff University, who met him many times, said: "He was very diffident and self-effacing. He always gave the impression of being quite surprised by his own celebrity."
Many people were baffled and frustrated by his theories, notably deconstruction, and this was compounded by his disinclination to define them succinctly.
Professor Norris, who called him the most original philosopher of the 20th century, said he refused to dictate what other people made of deconstruction, and was "very polite" if views differed from his. But he was irritated if people wilfully misrepresented him.
A group of Cambridge University dons tried to stop the university awarding him an honorary degree, and an international group of scholars wrote to The Times saying his work did not meet "accepted standards of clarity and rigour".
Roy Harris, emeritus professor of general linguistics at Oxford University, recalls attending a series of Professor Derrida's lectures at the Sorbonne.
"It wasn't until then that I realised what amount of effort he devoted to wilful verbal obscurity," he said. And added that he appeared to take Antoine Rivarol's comment, "What isn't clear, isn't French", as a personal challenge.
"Derrida's work has an enormous appeal to the intellectual anarchists and at the same time to the academic snobs, and that makes a very powerful combination," he said.