One Nation senator Malcolm Roberts was waiting but Alan Finkel was ready.
The chief scientist, who has a PhD in electrical engineering and worked as a postdoctoral research fellow in neuroscience, could see what Parliament's most persistent climate change sceptic was doing.
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Did Dr Finkel believe it was important for a scientist to keep an open mind, Senator Roberts wanted to know.
Dr Finkel spotted the trap and said he was happy to own up to a "healthy degree of scepticism".
"But healthy is an important word there," Dr Finkel told the senator in a committee hearing last week.
"You have to have an open mind, but not so open that your brain leaks out."
That no-nonsense, plain-speaking approach - delivered with extreme politeness and the hint of a twinkle in the eye - has taken Dr Finkel from his childhood consideration of medicine to academia, Silicon Valley, founding a science magazine, developing a secondary school science program, and, now, the Turnbull government's principal scientific adviser.
When the newly minted Prime Minister Malcolm Turnbull announced Dr Finkel's appointment, he could barely contain his enthusiasm. Mr Turnbull was so excited he hijacked the press conference to ask Dr Finkel his own questions.
Dr Finkel came to the job at a difficult time.
Mr Turnbull's predecessor, Tony Abbott, had scrapped the job of science minister and made large funding cuts to research and development.
Dr Finkel's predecessor, Ian Chubb, clashed with Mr Abbott's business adviser, Maurice Newman, who described climate change as a "scientific delusion".
Those sceptical about climate change within the Coalition were also sceptical about Dr Finkel.
After all, the man drives an electric car, powers his home with 100 per cent renewable energy and had, prior to his appointment, spoken of a future where coal-fired electricity generators are closed and internal combustion engines are replaced with electric ones.
Dr Finkel retains a delight and fascination with science most of us once had but lose as adults.
His enthusiasm extends to having a seat booked on the first commercial space flight complete with a ticket stamped: "First Chief Scientist in space."
Now Dr Finkel can add another item to his resume - political peacemaker.
His recommendation of a Low Energy Target (also known as a Clean Energy Target) looks set to bring peace to the climate wars that have ravaged policy in this area for more than a decade.
So vicious has the war been that it claimed the prime ministerships of Kevin Rudd and Julia Gillard and the leadership of Malcolm Turnbull when he was opposition leader in 2009.
Labor has offered its support for a target and business is desperately urging the Turnbull government to adopt the recommendation to bring long-term stability to climate and energy policy.
It would be a significant achievement for a man who said he took on the job of chief scientist because he wanted to be of greater public service.
All this for someone who has another three-and-a-half years in the position.
In his final speech as chief scientist, Ian Chubb warned scientists to be brave: "We know there are those who want only to be told what they want to hear. When they aren't, they simply denigrate and disparage and dream up conspiracies. I can only say to scientists: don't flinch. Do your work; do it according to the trusted methods of ethical science and talk regularly to the public . . . their support, and the weight and quality of evidence, must always trump make-believe."
They were words Dr Finkel clearly took to heart.