David Mitchell: The key is that ultimately, surely to save the environment things have to be made more expensive - the things that are destroying the planet have to be made as expensive monetarily as they are to the environment and that's going to involve a lot of sacrifice, don't you have to be honest about that?
Caroline Lucas: Well I will be honest about that, what I think it needs is a shift in taxation, not an overall increase in the burden of taxation, but if we taxed carbon instead of taxing income so much for example that would be a very good thing, we'd get more people into jobs, we'd also tackle the environmental crisis, so it's not rocket science...
This is a far cry from the Greens' general election manifesto that called for massive tax increases to close the deficit.
Whatever happened to "left wing plus"? Don't get me wrong here, I agree with the policy - but it is not a left wing one - the left much prefers taxing income to taxing consumption. I also agree with the question - if the Greens can't be honest about the sacrifices they expect, it is a bit rich to accuse other parties of being all talk and no trousers.
But more significantly, whatever happened to the Green Party being the last bastion of big tax and spend politics, appealing to the disaffected left? Is it really quite so shallow as to switch its whole politics from the hard left to the centre now it thinks there might be more mileage in attracting disaffected Lib Dems?
And has this monumental step really happened in an interview on a comedy news and politics show? Does the rest of the Green Party know anything about this? What do they think?
I am feeling a little stunned here.