David Yardley delivering an intervention for Australia at the United Nations Security Council, 18 December 2017.
David Yardley studied the MPhil in History and Philosophy of Science and Medicine in 2004. His subsequent career as an Australian diplomat has been extensive and varied, including serving as High Commissioner to Kiribati and in the role of Ambassador and Deputy Permanent Representative to the UN in Geneva. Throughout it, he has always found himself drawing from what he learned from the MPhil course.
With a diverse undergraduate background from the University of Sydney in Pure Mathematics, Law, and History and Philosophy of Science, he had to decide which discipline to take to the Master’s level. He landed on the Cambridge MPhil – not only did he find the subject stimulating, but he also found it best aligned with his ambition to make an impact.
“I had a strong desire to make a difference,” he explains. “Against a backdrop of learning about ‘how the world is’ through Law, History and Philosophy of Science helped me develop crucial skills that help think about ‘how the world could be’. It helps you reflect on what’s possible, especially by engaging your mind across incredibly diverse subject matter and theoretical approaches. As for choosing Cambridge itself, it was simply the best school in the world for the discipline.”
David Yardley speaking at the United Nations General Assembly.
Joining Cambridge
On entering the Department of History and Philosophy of Science, Yardley was immediately struck by its broad and open engagement with many different ideas.
“History and Philosophy of Science is a contested field,” he says, “but here, it was coupled with an environment of genuine intellectual curiosity, rather than sacred cows and dogmas. And there was an embrace of this field’s contested nature.”
He believes that this intellectual curiosity is maintained by the diverse academic and student body and the variety of perspectives they bring.
“There’s no end of enjoyment in those environments, but there’s also no end of insight you can draw from each other,” Yardley recalls. “We had an incredibly knowledgeable group of people get together for a seminar, where everybody had diverse strengths, perspectives and knowledge bases. And we really saw how cooperation amongst these intellectual strengths led to better things than competition.”
Yardley was also enthusiastic to work with researchers that he admired. The late Professor Peter Lipton, the first Hans Rausing Professor, had featured in his undergraduate research, and was a major source of inspiration. His decision to join this MPhil was partly due to Lipton’s presence, and he describes working with him as an immense privilege.
Yardley graduating from the MPhil in 2004.
Creating a thesis
Yardley credits Peter Lipton, who was also his supervisor, for inspiring his own thesis.
A significant part of Lipton’s research focused on the Inference to the Best Explanation approach in science. With deep roots including a relationship to the famous medieval ‘Occam’s Razor’, it emphasises how the confirmation of scientific theories relates to their explanatory quality – that scientists infer from the available evidence to the hypothesis which would, if correct, best explain that evidence.
An alternative outlook for understanding confirmation of scientific theories lay in Bayesianism, emphasising discovering the most probable cause of scientific phenomena via experiments that adjust ‘degrees of belief’ in a given theory.
Yardley’s thesis explored the potential for synthesis between the Inference to the Best Explanation and Bayesian approaches, recognising and bringing together the contrasting strengths of both – one with an emphasis on ‘quality’ considerations, one with an emphasis on ‘probability’ considerations.
Yardley also speaks fondly about developing and executing the thesis, as a process that also developed essential career skills. The process of formulating a complex idea, researching and debating the subject, and elaborating a novel argument within defined timeframes was a highly valuable exercise in long-term strategic thinking, management and delivery of a challenging project. It was qualitatively different from undergraduate level, and extremely useful in developing the skills to contribute at a high level in the modern workplace.
Yardley speaking at the HPS Careers panel, November 2025.
Work since graduating
Yardley’s career since graduating has been extensive and varied. From a graduate position in the Australian Department of Education, Science and Training, after a few years his career moved into Australia’s foreign service, and has since involved extended time serving overseas, including in Afghanistan, at the United Nations in New York, in Kiribati and Geneva. This has included Ambassador-level appointments in recent years – first as High Commissioner from Australia to Kiribati, and more recently a period working as Australian Ambassador and Deputy Permanent Representative to the UN in Geneva.
As High Commissioner to Kiribati in the challenging time of COVID-19 for example, he led Australia’s in-country development efforts in partnership with the Government of Kiribati, on a vast array of issues, from provision and rollout of COVID-19 vaccines, to school-building on the outer islands of Kiribati, to solar-powered distillation plants and other climate adaptation and mitigation, to support to maritime security in combating illegal fishing and many other areas.
“Those years were a highlight for me,” says Yardley, “you could really see the difference your work was making right in front of your eyes.”
David (second from left) with Australian, New Zealand and I-Kiribati representatives including President Maamau (fourth from left), during the handover of the first Guardian-class patrol boat from Australia to the Republic of Kiribati.
He credits his MPhil course and studies in History and Philosophy of Science for honing many of the skills that helped him deliver in these and all career positions. He highlights three skills in particular from the MPhil: critical thinking, adaptability, and creativity.
“Many disciplines point to the idea that they teach ‘transferable skills’ – which is true,” he explains. “But in History and Philosophy of Science, developing and optimising those transferable skills is right at the centre.”
Across a diverse career, with vastly differing demands depending on the location and focus, being effective has meant engaging every day with different inputs, new information and circumstances, different types of data, some qualitative, others quantitative, while working effectively with truly diverse groups of people. The MPhil was excellent preparation for that kind of challenge - every week we were adapting to unfamiliar issues, engaging critically with different approaches and disciplines, and exercising creativity drawing from a wide range of perspectives and prior knowledge.
He emphasises that these skills would have been invaluable in any job, with flexibility increasingly critical in modern employment.
“Today, information – and misinformation – is cheap and at our fingertips,” he explains, “and the thing that I think is increasingly in demand is those transferable skills, like critical thinking, adaptability and creativity.”
In his opinion, this is a key part of what makes the MPhil in the History and Philosophy of Science and Medicine an excellent course: it focuses centrally on strengthening those abilities.
“It is an amazing and diverse discipline in its own right, full of stimulating and valuable issues and lines of inquiry,” he says. “But I also think it helps equip you with the skills and temperament to make a positive difference beyond academia, out in the world.”
David with I-Kiribati scholars who studied under the Australia Awards scholarships, and I-Kiribati representatives, including Vice-President Toatu (centre).