Audit your own beliefs: the one that failed was the one my income depends on

I have a rule for everything I publish: never write a number, a date or a claim I have not seen the source for. It has been useful. It has also been comfortable, because it governs what I say rather than what I think.

So in August I turned it inward and ran it against beliefs I actually hold. Not positions I argue in public. Things I would have told you were true if you had asked me over a coffee.

Three of them so far. One survived in a much narrower form than I held it. One came back wounded. And one could not be stated in a way that could fail at all, which is the interesting one, because it is the belief my income for the next year rests on.

Why this is harder than it sounds

The obvious explanation for why people do not examine their own beliefs is that they are lazy. It is the wrong explanation, and it is worth replacing, because it makes the problem look like a character flaw rather than a mechanism.

Here is the better one. A belief you have held for a while stops being something you carry and becomes part of what you are. Once that has happened, someone questioning the belief is questioning you. The response is not curiosity. It is the physical, defensive thing you feel when somebody criticises your work in front of colleagues.

There is a research literature on this under identity-protective cognition, and the finding that makes it worse is that being better educated does not reliably help. It gives you more sophisticated tools to defend what you already think.

Which means the fix cannot be more rigour applied to the same self. It has to be a different self-description: not a person who holds correct views, but a person who tests views. Then somebody attacking one of your beliefs is doing you a favour rather than an injury, and you can defend it hard without needing it to win.

That is a much bigger ask than "be more careful", and I want to be honest that it is the ask.

Somebody who did it

Thomas Sowell spent his twenties as a Marxist. Not casually. He held it through Harvard, through a master's at Columbia, and through a doctorate at the University of Chicago taken while sitting in Milton Friedman's classroom. None of that moved him, which tells you something on its own about how far argument gets you.

What moved him was a summer job.

As a graduate student he interned at the US Department of Labor and was put on minimum wages in Puerto Rico. As the minimum wage rose, employment fell. Two explanations fitted the data equally well: workers priced out of their jobs, or hurricanes destroying the sugar crop during harvest. Chicago had taught him that when two theories compete, there is usually a measurement that separates them.

He worked out what it was. How much sugarcane was standing in the fields before the hurricane struck.

He asked for the number, expecting to be congratulated. In his telling he got stricken faces, then a chain of command running from the Secretary of Labor to the Secretary of Agriculture and back, and then nothing. He says he is still waiting.

Two things in that story are worth more than the conclusion he reached.

The first is his own account of what changed him: he did not raise his standards, he applied the ones he already had. That is what an audit is. Not becoming more sceptical. Pointing existing scepticism at something it has been carefully avoiding.

The second is why the number never arrived, and it is not that anybody lied. The department administering the minimum wage had budgets and careers resting on the answer. An institution does not have to deceive anyone to make a question expensive to ask.

What happens when nobody does it

The second case I want to give you comes with a warning attached, and the warning is the point.

The economic historian Phil Magness argues that Marx's standing has almost nothing to do with his economics winning an argument. On his account, Das Kapital was published in 1867 and sold badly. Marx died in 1883 without the recognition he thought he was owed. The marginal revolution had meanwhile solved the theory of value a different way, and when economists finally engaged with him seriously it was to conclude the foundations were obsolete. By the early twentieth century the profession had answered him and moved on. What made Marx ubiquitous was not the argument. It was a state adopting him after 1917. He is now most assigned in the disciplines least equipped to assess the economics.

Now the warning. I have not checked those specifics at source. I have the publication date and the death date, which are not in dispute. The rest is Magness's account, he holds a chair at a free-market think tank, and he is arguing a case rather than reporting neutrally.

I could have dropped that paragraph and the piece would read more confidently. But an essay about claims that travel without their evidence cannot itself pass on a claim without its evidence, and telling you exactly where the line falls is more useful to you than a smoother sentence.

What I will say is that the shape is checkable, which is more than most things you will read this week.

One of mine

Here is a belief I held: generous welfare transfers create dependency and reduce people's capacity to lift themselves out of poverty.

I would have told you that was empirical rather than political, and I would have been sincere. When I actually went looking, the first finding was not about the evidence. It was that in a vault holding several hundred notes, I had never written anything down about it. No sources, either way. Not one.

Splitting it into two testable claims made the problem visible immediately.

On labour supply, the strongest evidence is real and it is smaller than the belief. Vivalt and colleagues randomised a thousand low-income Americans to $1,000 a month for three years against a control group of two thousand receiving $50. Labour market participation fell 4.1 percentage points and hours worked fell roughly 1.3 per week (NBER Working Paper 32719, 2024). That is a genuine effect in a rich country with a meaningful transfer. It is also not a lifestyle. Meanwhile a pooled reanalysis of seven randomised trials of government cash transfer programmes across six countries found no detectable effect on the propensity to work or on hours, for men or women (Banerjee, Hanna, Kreindler and Olken, World Bank Research Observer 32:2, 2017).

On the self-lifting half, the evidence largely runs the other way. Akee and colleagues studied an unconditional per-capita casino dividend paid to the Eastern Band of Cherokee. An extra $4,000 a year to the poorest households raised educational attainment by a year by age 21 and cut the chance of a minor criminal offence among 16 and 17 year olds by 22 per cent (American Economic Journal: Applied Economics 2:1, 2010).

And something did survive, which matters as much. Dahl, Kostøl and Mogstad used Norway's disability system, where appeal judges are randomly assigned and differ in leniency. When a parent is allowed disability insurance on appeal, their adult child's participation in the same programme rises six percentage points over five years and twelve after ten (Quarterly Journal of Economics 129:4, 2014).

So the belief did not die. It narrowed, and it changed subject. What is left is a claim about programme design: transfer schemes whose eligibility gate is a status claim, or whose benefits phase out steeply against earnings, produce modest reductions in measured work and, in the disability case, pass participation to the next generation.

That is not the belief I held. The version I held was about people. The version that survives is about incentive structures, and I already had the tool that would have got me there years earlier. I had just never turned it on myself.

The one that would not stand up at all

The third is the one I would rather not write about.

The belief: regulated financial services buyers will pay me premium day rates for resilience and AI advisory work after I go independent.

The audit never reached the evidence stage. It could not, because I would not name a rate or a date by which a first paid engagement had to land. Without those, no result could ever contradict it. Any disappointing month becomes early days.

When pressed, I said the belief was not carrying much weight just now. That was a dodge and it is recorded as one, because it is the belief the whole income plan rests on.

I want to be precise about what is wrong here, because it is not optimism. Optimism is fine and is arguably required. The problem is that the belief is shaped so that it cannot fail, which means it also cannot tell me anything. I get no signal in October, none in November, and no moment where the honest response is to change the offer.

The fix is not to believe it less. It is to give it a number and a date, so it can be wrong on a Tuesday and I can find out.

The pattern across all three

The thing I did not expect: rigour was inversely correlated with how strongly I held the belief. The one I could state most precisely was the one I depended on least. The ones carrying real weight had the least written evidence behind them.

That is not a character flaw, it is what the identity problem looks like from the inside. The beliefs doing structural work are the ones examining them destabilises, so they get examined last, or never.

If you want to do this

Four steps, a couple of hours per belief.

State it so it could be wrong. Not "I think X is broadly true", but the sentence a result could contradict. If you cannot write that sentence, stop. You have already found something more important than whatever you were going to find next.

Predict before you look. Write down what you expect the evidence to say. Otherwise whatever you find will feel like confirmation.

Find the strongest opposing case, not a straw one, and note whether you had ever met it before. I had not, and the leading opposing source was a World Bank publication rather than anything obscure.

Say what would change the verdict, and by when. A belief with no such condition is not a belief you hold. It is a belief that holds you.

One line keeps coming back to me, from two educators arguing about why people avoid conversations they disagree with. The charitable reading is that some people dislike conflict, which is temperament rather than cowardice.

The reply stuck. Then should they not hold those beliefs more lightly?

If you are not willing to have a belief tested, that is not an argument for holding it harder. It is an argument for holding it more loosely.

I have four more on the list. The next one is about climate coverage and I am not looking forward to it, which is probably the reason to do it next.