When I saw the clip of 16-year-old climate activist Greta Thunberg speaking at the UN I bristled.
A critical voice in my head spoke up.
"Why is she so overly dramatic?" the voice said.
"I bet it's not going to be as bad as she said. I bet it takes longer for things to get really bad, things always do."
The voice in my head got louder.
"Why is she so dismissive of everything that works well in society?"
"She says we should stop thinking about money - doesn't she know that we're going to need money and capitalism to fix this crisis."
"Doesn't she see that technology is the only way through this?"
Now the voice was shouting.
"I don't see Venezuela doing much to solve climate change," the voice said.
"Young people are annoying," it said.
It was the voice of an angry old white man.
The angry old man lives inside me. He's reactionary and defensive.
He doesn't like change and I hear him getting louder as the years roll by.
He's technically right about a lot of things, but he's almost always on the wrong side of history.
I don't like him much.
Critical thinking is crucial to human success. We need to apply it rigorously.
But if we keep our focus narrow enough it can become a useful tool to avoid seeing a much bigger picture.
Keeping our focus narrow makes conservatism easier. It allows us to push back against change.
For some reason we get better and better at that as we age.
You'd think with so much less time left on the planet we'd be getting more care free.
We've done the hard yards, we're financially secure. The stakes should be getting lower.
Instead we focus on all we have invested in the world. We want to hold on to it.
Conservatism can be synonymous with wisdom. It can stop us making mistakes and sometimes it is good to share.
But it should be shared without anger.
And when the evidence is clearly in favour of the need for change - as it is with climate change - it can become a problem.
Thunberg's passion for change seems deeply triggering for many older men.
It has prompted an aggressive backlash on social media and from some conservative commentators.
That depth of feeling about Thunberg isn't surprising to me - but it is a little embarrassing.
I recognise the appeal of conservatism. It is like a warm blanket. It provides an almost religious comfort for those who enjoy the status quo.
Its arguments encourage us to relax, stop worrying, shed any burden of guilt.
I am middle-aged and privileged enough to be lazy about social change.
But on balance I'm glad that young people are getting politically fired up.
So if you are a male of certain age, if you feel angry and antagonised by what young people are doing and saying, maybe it's time to stop and take a moment to think about what it is that specifically upsets you.
Are you giving in to the old man inside your head?
When previous generations marched for civil rights or against apartheid, which side were you on?
It doesn't matter if you are 45, 65 or 85 - you have the power to remember what it meant to be young and see only the big picture. Doing that might help keep you young.
Thunberg's speech reminded me of the profound words of a 78-year-old man.
He wrote them when he was 22.
After all these years they are as relevant now as they ever were.
Admit that the waters
Around you have grown
And accept it that soon
You'll be drenched to the bone
If your time to you is worth saving
And you better start swimming'
Or you'll sink like a stone,
For the times they are a changing
- Bob Dylan