Hypnotist Paul McKenna has launched a libel action against the Daily Mirror newspaper over claims he was "a fraud".
Paul McKenna is expected to take the stand on Tuesday
The High Court case is expected to last a week and Mr McKenna is due to take the stand on Tuesday.
The 43-year-old TV hypnotist disputes an October 2003 article, which mentioned his "bogus degree" from Lasalle University, Louisiana.
He claims he was "pilloried" by journalist Victor Lewis-Smith on around 10 occasions from 1997.
Paul McKenna runs a self-help business, whose clients include Saatchis and law firm Freshfields.
The case is being heard Mr Justice Eady without a jury.
Mr McKenna's counsel, Desmond Browne QC, told the court: "Victor Lewis-Smith and the Mirror pilloried Mr McKenna as a fraud, claiming that he had a doctorate to which he had no honest entitlement.
"They can't prove that to be true."
He said that the newspaper, which denies libel, had defended a grave allegation of fraud and dishonesty with "increasing desperation and inconsistency".
Mr Browne said that Mr McKenna, a dyslexic, sought a PhD to make up for his failure at school, to make a contribution to the community which would have practical therapeutic benefits and to add value to his business.
He said that far from being able to buy a doctorate, the evidence showed that Mr McKenna was initially rejected for the course.
The fact was that at the end of 1996 - although Mr McKenna did not know this until later after he had submitted his final project - it emerged that Lasalle was only accredited by a body called the Council for post-secondary Christian Education, which turned out to be a fraudulent creation of the university's founder, Thomas Kirk.
Investigations by the FBI and the US Department of Justice concluded that Kirk had defrauded innocent unsuspecting students by leading them to think that their degrees were accredited by a recognised body.
"The judge who sentenced Thomas Kirk referred to the innocent victims of this fraud, and one of them was Mr McKenna," he said.
He said that Mr McKenna tried to resolve his difference with the newspaper sensibly without recourse to litigation but it was the newspaper's own intransigence and obstinacy that finally drove him to issue proceedings.
The newspaper was not saying that McKenna was a charlatan, claimed Mr Browne, but was suggesting that he either knew his degree was bogus or was reckless as to whether it was.
The case continues.