I once had the good fortune to spend time with the great behavioural economist, Daniel Kahneman. In passing, he mentioned that at least 98 per cent of the things we believe, we believe for no other reason than someone has told us they are true. Of course, there simply isn’t time for us to verify everything for ourselves. Furthermore, our competencies are limited, so aren’t we better off listening to experts?

It seems pretty reasonable, but I think danger lurks here. One could make a very strong case that the Enlightenment in general, and science in particular, began with Descartes’ radical insistence that we shouldn’t accept anything second-hand. Descartes set out to identify a method that could reliably separate truth from falsity. An essential component of his method was doubt: doubt everything and take nothing on authority. This was the seed from which the scientific revolution grew.

It’s easier to trust the word of someone who agrees with us

The driving force of (what we now call) science was the need to answer questions that emerged in the day-to-day business of life: How can I tell if a crown is made from pure silver? When will high tides come? How do we maximise crop yields? How can we make more accurate weapons than those of our enemies?

Although he didn’t identify this himself, a significant corollary of Descartes’ method was that no claim could be legitimate unless it had concrete implications in everyday experience. Unless, in other words, there was an accessible and unambiguous way to determine whether that claim was correct. Seems like common sense, doesn’t it? Well, this was in stark contrast to the dominant theological approach of the time. Religions habitually instruct us to forsake our own experience and allow ourselves to be guided by the pronouncements of the initiates. The consequence being that no statement, no matter how ludicrous, can ever be refuted by experience. There’s a brilliant parody of this in Brideshead Revisited:

“So you understand the dogma of papal infallibility?”
“Oh yes, Father.”
“Suppose the Pope says that it’s going to rain tomorrow. Does that mean it will rain?”
“Oh yes, Father.”
“But supposing it doesn’t rain, what then?”
“Well… uh… I guess it would be, ah, spiritually raining. Only… We were too sinful to see it!”

Questioning the authority of the initiates was, of course, heretical; debate was systematically closed down by the threat of eternal damnation. However, with the ascendency of experience came the death of authority; leaving the charlatan with nowhere to hide.

The emancipatory effects of all this were massive.

Unfortunately, this happy state of affairs didn’t last. As science became more and more specialised, it was inevitable that its postulates would recede further and further from everyday experience. Do you believe in atoms? You’ve never seen one. What about protons? How about a black hole? Ever experienced a shifting continent?

As science became ever more abstruse, everyday experience began to lose status. Eventually, it became subservient to the words of the expert. This meant that Argument from Authority was able to sneak back in, as ever, donning the garb of inaccessibility: “Don’t trouble yourself with this, it’s beyond your ken.” Once again, we were instructed to eschew our own experiences and accept the words of the initiates. It was they, and they alone, who could understand what was really happening.

However, no discipline is immune to sociological forces, political agendas, financial incentives, or power dynamics. Accordingly, a genuinely disinterested researcher is a rare beast. This, I suspect, is especially the case with research that has direct policy implications. So where’s the safety net? We certainly need one.

Under the Enlightenment picture, doubt and verifiability provided the bulwark against the incompetent and the malevolent. Absolutely anyone was competent to ask of a scientific claim: Is this claim logically consistent? Is it consistent with my experience? Now, however, only the qualified may ask questions, and anyone whose experience doesn’t fit the consensus is strongly encouraged to disregard that experience. To do otherwise is modern-day heresy.

The growing rift between science and everyday experience means the question is no longer: How can I tell if this is true? Instead, it’s: Who should I trust? So, instead of rival theories being put to the tribunal of logic and our own experience, we have look to the credentials of the person advocating that theory. Unfortunately, it seems to be a great deal easier to trust the word of someone who agrees with us than of someone who doesn’t. And for many, an agreement with our existing position has become the most important credential of all: the very antithesis of a scientific approach.

Peter Lawlor is the Principal Economic Advisor to 7Ridge Capital and an adviser to senior Wall Street figures. These are strictly his own views