And experiencing that it was clearly not the case. A lot of people feel quite hopeless, I think, at this realisation.
I got curious. I am an active problem solver. I wanted to see what the evidence said about what could change that.
What I found gave me a lot of hope. Hope that it is possible for good knowledge to be used to improve lives if we use effective tools.
It is this hope I wanted to share with the book.
So what, in your view, has brought about the rise of the post-truth climate we now live in?
It is a threefold problem and two of these are not new to humans.
Firstly, information is manipulated by powerful people, or those wanting power or influence.
That has always been true and humans have always responded to it for various reasons, including just liking to gossip.
Secondly, none of us process information by first weighing up the pros and cons of the information people present to us.
The rationalist model is a really enduring but incorrect one. We filter all new information through our values and beliefs first.
If it fits with what we already know then it feels good, if not it feels bad and we reject it.
We still apply logic but only after these other more instinctual and unconscious processes.
I would say that even the accepted idea of rationality is a very western cultural belief system. So human bias is not new.
What is new are the digital tools and media that can spread misinformation so very powerfully.
Which is the third problem the power of these tools to spread misinformation.
Misinformation gets in front of us repeatedly and is more outraging and novel often than good information.
So it means that the environment for information is very unbalanced.
It does not support people seeing and believing good information - less post-truth and more a barrier to the truth.
What are the big risks that come with it - and how can these directly affect us, directly or indirectly?
Mary Beard is one of my favourite historians and cultural commentators.
She points out that this experiment we call democracy is a very long and slow one, and yet to be perfected.
Part of what needs work is the role good information and misinformation plays in decision-making in our democracy.
Fully participative and inclusive democracies do require people to be able to see, hear and believe good information and then make decisions based on that.
It is dangerous to assume that just putting good information into the public domain is enough to make that happen.
On a more interpersonal level misinformation can be intentionally polarising.
That is, it seeks to push people to the extreme ends of their thinking and beliefs.
That makes it incredibly hard for people to find what they have in common, our shared values - of which we have plenty.
And finding those shared values are critical for not just the big problems of our time, but also just in our communities and own families on a day to day basis.
We know that misinformation travels further and faster than good information, much like a virus. Why is this - and what is it about human behaviour that predisposes us to fake news or dodgy facts?
Some of this is about, as I said, our filtering of information through existing values and beliefs.
And how feelings, including the physical responses we have, act a traffic light to tell us to accept or reject new information.
We apply logic only after we have applied beliefs and emotion.
We also have something called a truth bias. We tend to generally accept most information as true unless we have a clear reason not too.
That is part of being social creatures. Repetition also has a strong impact.
If we see the same ideas from multiple sources, and we trust those sources, it tends to become embedded.
Once misinformation gets in it is very hard to shift. We create strong narratives based upon it.
So simply replacing bad information with good information is ineffective.
Do you feel New Zealand is any more vulnerable to this than other Western countries?
I don't think there is anything particularly unique about New Zealand brains, so in that sense all humans are at risk of misinformation.
I will say that in an area such as vaccination the partnership approach to communicating vaccination has made us resistant in some ways - only four per cent of people activity decline childhood vaccinations in New Zealand.
We have done lots of outreach and working with communities and listening to parents, so we are possibly more resistant to flare-ups of misinformation in that space.
To elaborate on something you said earlier: the past two decades have been an increasingly challenging for traditional media, while social media has flourished. How much blame should the likes of Facebook get for enabling the rise of post-truth and fake news? Can these social media companies be trusted to be as responsible with facts and transparency as the institution of journalism long has been?
Honestly, no, they can not be trusted.
Social media companies have had plenty of opportunity to prioritise social and environmental wellbeing, to focus on ways to provide good information and shut down misinformation, and they have not.
I think there is also a danger to traditional media from this - that is adopting the model that social media has in order to compete.
There are so many dedicated and committed people in journalism.
But we are all subject to forces of a system and so there is a risk there.
I will say that journalists have picked up pretty quickly the risks of false balance reporting in this changed environment and adapted their style accordingly.
Social media does have many benefits, including the opportunity to hear and listen to others experiences who we would not normally.
So finding ways to shape the tool for better outcomes is really important.
What hope do you have in society over-coming the post-truth problem - and what are some basic ways we can counter it?
Oh I am very hopeful.
As Jo Cox said we really do have more in common that the polarised environment lets us see. Research shows that.
And very few people are absolute in their beliefs. We all hold a wide range of beliefs and have it in us to prioritise different values and beliefs with the right support.
Basic approaches include not sharing polarising content, focusing on talking to the silent majority of people who do not comment on the internet, and giving more amplification to positive stories.
People have 99 problems, giving them another one without a positive solution is not going to move them.
Consider building new narratives around your evidence instead of refuting someone else's bad evidence.
Work with your sector to develop effective narratives to amplify and repeat.
I do think media producers need to consider very carefully the amplification given to misinformation and misinformed voices in the context of the unbalanced information environment and human bias.
There are lots of tips and techniques in the book.
I wanted it to be practical for scientists, researchers, advocates wanting their good information to be used in decision making.
Lastly ... if there's an easy take-home from your book, what is it?
Start talking about shared values before talking about evidence.
The types of values that encourage people to see the usefulness of acting together on issues like climate change or inequality.
Fact fights won't win the day because disagreements over facts are seldom about facts.
They are about what matters most to us.
• Dr Jess Berentson-Shaw - A Matter of Fact: Talking Truth in a Post-Truth World. BWB Books; RRP $14.99.