Just wrapped up another two days of public hearings in Canberra on the Greens-Labor inquiry into “Information Integrity on Climate Change and Energy”.
This is my session with Dr Karl. What do you think of his behaviour?
He asked me whether I thought the past 10 years have been the hottest on record globally I replied directly “No, I don’t”. He responded with mockery and ridicule, then shifted the topic to what he claimed is a “99.999% consensus.”
By the way, consensus is a political tool. Instead, science is decided using data. I replied with actual data.
Later Dr Karl admitted science is “never settled” – when it suited his Newton/Einstein analogies. Yet he refused to acknowledge the actual historical climate records from our own 1880s.
It seems that he’s more interested in “elitist” condescension than hard facts. Notice how he has many tricks for avoiding answering questions or changing the topic.
Real integrity requires debate, not evasiveness and dismissiveness.
– Public Hearing | 16 February 2026
Transcript
CHAIR: I might go to Senator Roberts.
Dr Kruszelnicki: Senator Roberts, good afternoon.
Senator ROBERTS: Good afternoon, Dr Karl. Can I call you Dr Karl?
Dr Kruszelnicki: Or Karl; it doesn’t have ‘Dr’ on the birth certificate.
Senator ROBERTS: I’ll call you Dr Karl. You may remember that I issued a challenge to debate, and you were the only person who took it up. Then we met on South Bank because you wanted to explain to me why you were going to pull out of that debate. We spent about three-quarters of an hour together, back on Sunday 26 March in 2017. Can you recall that in South Bank?
Dr Kruszelnicki: I remember the event; I didn’t keep a record of the date. My memory is not that I was trying to explain where I was coming from or why I didn’t want to do a debate. My memory is quite different. I wanted to understand where you were coming from, and you explained it to me and we had that talk, off the record, so I’m not at liberty to reveal what you told me.
Senator ROBERTS: Okay. Let’s talk about science—
Dr Kruszelnicki: Sure.
Senator ROBERTS: and some definitions. I just want to get your confirmation or otherwise. When done properly in accordance with the scientific method, science uses rational thought and logic to investigate and explain our physical world—is that correct?
Dr Kruszelnicki: Ish. When you’re talking quantum mechanics, which is real, it doesn’t work. But that’s a good mark 1 definition, sure, as a first approximation. Yes.
Senator ROBERTS: Thank you. Science is the systematic, objective, rational study of our physical world through observation, experimentation and testing of theories against the empirical data.
Dr Kruszelnicki: What’s that word ’empirical’? I’ve noticed that you love that word ’empirical’ to pieces.
Senator ROBERTS: I sure do.
Dr Kruszelnicki: Can you define it for me, please.
Senator ROBERTS: Sorry?
Dr Kruszelnicki: Can you define the word ’empirical’ for me, please.
Senator ROBERTS: Yes, sure. It’s measured or observed data.
Dr Kruszelnicki: But, if you’re saying ’empirical data’, it’s just like saying ‘data data’. Okay. Go on.
Senator ROBERTS: Empirical data is measured or observed. There are many other things in social sciences which are not.
Dr Kruszelnicki: Well, come on. We’re talking physics here.
Senator ROBERTS: Correct. So you agree.
Dr Kruszelnicki: Yes and no, but go on. Mostly. That sounds like a good start, except for the word ’empirical’, but go on.
Senator ROBERTS: Scientific proof involves using solid data as evidence in logical scientific points to prove cause and effect. So it’s not only having physical data; it’s putting it within a logical scientific point that proves cause and effect.
Dr Kruszelnicki: Are you building a little assembly where you’ll suddenly say, ‘And therefore climate change isn’t real,’ and I’ll fall over unconscious?
Senator ROBERTS: Why do you think that?
Dr Kruszelnicki: You’re laying out a boilerplate set of logical debating steps. Hit me with the next one.
Senator ROBERTS: Do you agree or not?
Dr Kruszelnicki: Overwhelmingly yes, depending on the data, because it doesn’t apply to quantum mechanics.
Senator ROBERTS: I’m assuming the data is accurate—data within logical scientific points proving cause and effect.
Dr Kruszelnicki: Let’s see if we can agree on something. Do you agree that the climate records show that the last 10 years have been the hottest on record worldwide?
Senator ROBERTS: The last 10 years in Australia have been cooler than the 1880s and 1890s in Australia.
Dr Kruszelnicki: Hang on—worldwide. Do you agree that the last 10 years have been the hottest years on record worldwide?
Senator ROBERTS: No, I don’t.
Dr Kruszelnicki: I feel like I’m talking to a schoolchild who says seven times two is not 14 but instead seven times two is a bicycle divided by the square root of a banana.
Senator ROBERTS: That’s one way of making out that I’m a fool.
Dr Kruszelnicki: No, but all the scientists disagree with you; 99.999 per cent of the scientists disagree with you.
Senator ROBERTS: So now you’re into consensus, which is a political tool. Let’s continue.
Dr Kruszelnicki: Hang on. Consensus is a political tool?
CHAIR: Scientific consensus is not a political tool.
Senator ROBERTS: Is this correct: scientific proof is—
Dr Kruszelnicki: So, if all the scientists agree that seven times two is 14, that’s a political tool?
Senator ROBERTS: That’s obviously a stupid comment, in my opinion. Einstein said it takes one person to prove him wrong, even if 100 agree with him.
Dr Kruszelnicki: He’s dead right.
Senator ROBERTS: Thank you. Scientific proof is the basis for understanding nature and the physical world. Is that correct or not?
Dr Kruszelnicki: Pretty correct, yes.
Senator ROBERTS: Thank you. Science is never settled; it’s always enhanced in the future as new knowledge is unearthed and science is debated. A key point of science is debate.
Dr Kruszelnicki: Yes and no. With regard to gravity, the big step forward was Newton. Newton finally understood what was going on, but his theory of gravity could not explain why the closest point of approach of the planet Mercury to the Sun would tick around slowly over the decades. They measured this, and they couldn’t work out why. They had to hypothesise a planet. It was Einstein’s theory of gravity that then explained what was going on. So Newton was not disproved, but he was a small subset of a bigger, more comprehensive theory. In the same way, with Einstein, his theory may well also become a small subset of a bigger theory. You don’t go back. There’s no way we’re going to disprove Newton’s rule that the force between two bodies equals G times m1 times m2 all over r squared. There’s no way that’s going to get disproved.
Senator ROBERTS: Isn’t it true, though, that, some hundreds of years ago, people thought the Sun revolved around the Earth? That was the science.
Dr Kruszelnicki: Some did; some did not.
Senator ROBERTS: Then it was proven that the Earth revolves around the Sun, so science is always advancing.
Dr Kruszelnicki: And do you know why?
CHAIR: That was before there were 40,000 climate scientists studying climate sciences.
Dr Kruszelnicki: It’s because they were able to get optical instruments to look at the phases of the Sun upon Venus, and Venus had phases, if you know what that is—so sometimes there’s more of it on one side than the other—and the only way to explain that was by a central sun.
Senator ROBERTS: We could have a long, long talk about the intricacies, but those are the only questions I had.
Dr Kruszelnicki: Excellent. Can I ask you a question?
Senator ROBERTS: Sure.
Dr Kruszelnicki: Can you just refresh for me: thinking of the atmosphere as a one-kilometre line with nitrogen making up roughly 800 metres and oxygen making up roughly 200 metres, can you take me through where carbon dioxide sits in that line, by your estimation?
Senator ROBERTS: Carbon dioxide is 0.04 per cent of Earth’s atmosphere.
Dr Kruszelnicki: So how much of that line—one kilometre long—does carbon dioxide roughly make?
Senator ROBERTS: My maths doesn’t come to—is it a kilometre or a mile?
Dr Kruszelnicki: We’re going for a kilometre.
Senator ROBERTS: A kilometre—0.04 per cent.
Dr Kruszelnicki: There’s a million millimetres. I seem to remember you once saying, firstly, with the carbon dioxide bit of that one-kilometre line—with oxygen making up roughly 200 metres and nitrogen making up roughly 800 metres—that the carbon dioxide was so small that you could barely see it with the naked eye. The supposed addition, you said rather poetically, was kind of like how, if you rubbed your fingernail against some concrete, the little bit that rubbed off would be the addition of carbon dioxide that has been measured. Is my memory incorrect?
Senator ROBERTS: Sorry, what was that last bit?
Dr Kruszelnicki: Is my memory incorrect?
Senator ROBERTS: What did you say that I said?
Dr Kruszelnicki: My memory is that you said the carbon dioxide level was so small you could barely see it with the naked eye—
Senator ROBERTS: You can’t see carbon dioxide, it’s colourless. Carbon dioxide is colourless, odourless, tasteless.
Dr Kruszelnicki: Correct, but on that one-kilometre line, what length? My bad—you said the length was so small, it was barely visible to the naked eye, whereas, for example, the length of nitrogen was roughly 800 metres—easily visible. Is that correct, or is my memory wrong?
Senator ROBERTS: What was that about a fingernail?
Dr Kruszelnicki: Then you said that the additional carbon dioxide that has been added was roughly equivalent to getting a fingernail and rubbing it on concrete, and the little bit of fingernail that came off was that one-kilometre line, or the extra bit of carbon dioxide.
Senator ROBERTS: No, that wasn’t me. I don’t know who said that.
Dr Kruszelnicki: No worries. Thank you for clearing that up.




