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So I got pulled into economics in 2007 because of the 2008 economic crisis. Mike Brown who
had been the first CFO of Microsoft, Chief Financial Officer of Microsoft and treasurer
of Microsoft, he came to Toronto in 2007 and took my wife and I out to dinner and said
he was trying to put together a research group to work on economics and he would like me
to be involved. And I said, "I don't know anything about economics." And he said, "That's
okay because nobody does and the whole system is about to collapse." He said, "The balance
sheets of all the big investment banks -- it's like they have cancer. They're full of holes."
And I remember being very struck by this because this was before anybody was talking about
this.
And so I started to meet with a group of people that he was pulling together to understand
what was gonna happen and to understand if there was any way to save the situation. It
was a very ambitious thing and, of course, we failed. But along the way I was motivated
as a kind of public service to get interested in economics.
And what I found . . . economics, in a way, is very easy for a physicist to understand
because it's very mathematical. And the mathematical models that they use are very clean. They're
based on assumptions and hypotheses, and you can study them. And as I studied it I began
to understand, some for myself and more from just reading around because the faults with
the standard economic models, with the standard models of finance, are well known. They have
been in the literature for decades and decades. So let me give some examples.
The standard model of economics is called the neoclassical model and it assumes that
markets or systems where trading happens between consumers and firms and there's certain simple
models of how that goes on. And the ideas that these come to equilibrium. Equilibrium
not in the physical sense but in special economic sense in which you reach a point at which
the prices are fixed such that market forces fix the prices such that you maximize the
happiness of the consumers and maximize the profits of the firms. And in so called equilibrium
nobody can become happier or more profitable without somebody else becoming less happy
or less profitable. And the ideology behind this -- not behind the mathematics because
mathematics doesn't have an ideology -- but behind the arguments that were made and still
are made from this model is that markets don't need regulation because they have these natural
equilibria where everybody benefits to the maximum possible. And if you're in equilibrium
you can't do better.
Now there's a fault with this and it's an obvious fault and it's been known since the
1970s from some theorems proved by some economists including some of the founders of this field
of mathematical economics, which is that there's not one equilibrium, there are many equilibria.
In fact, there's a vast number of equilibria. And so which equilibria, even assuming that
this is a decent model of the economy which is not clear, but even assuming it's a good
model, which equilibria you're in depends on the past history, it depends on regulation,
it depends on politics, it depends on taste, it depends on changing taste, changing preferences.
And so history matters and what's called path dependence matters.
This takes us outside the neoclassical model of economics but it doesn't take us outside
of economics because some wiser economist, for example, Brian Arthur had for years been
developing models and theories of path dependent economy where the history does matter. People
from the area of complex systems like Stu Kauffman, Prubac in developing models of markets
where the history matters, where there's not a single equilibrium, where there are many
equilibria. And where change is paramount.
Another symptom of this is the idea that arbitrage isn't, I mean, in these neoclassical models
when you go to equilibrium, arbitrage is impossible. Arbitrage is making a profit from trading
around a circle of goods or a circle of currencies without actually producing anything. And in
equilibrium that's supposed to be impossible but lots of firms and investment banks made
fortunes off of currency trading, so why is that? It turns out because you're never really
at equilibrium.
So why is the notion of equilibrium so powerful? I think part of the answer is this idea of
physics envy, that economists thought that what they're doing was more scientific, hence
more correct, if it looked like physics. And physics had this timeless picture in which
what really mattered, as we were saying before, is the whole history of the system. And in
physics there's also a big notion of coming to equilibrium which is, although however,
it's important to say, a different notion of equilibrium. And somehow people in economics
got seduced into this model which again works in the small -- if you have a small little
corner of the economy, a small market -- it may work for a while to characterize approximately
what's going on. Arbitrage is not always there. It's not always, I mean, arbitrage, arbitrage
does get eaten up. There are market forces which do push you towards equilibria. There's
some truth in it.
But the whole thing is a disaster if I can say that as an outsider. And it led indirectly
-- it wasn't the only reason why regulations were lifted on markets and trading through
the decades, but when people were making arguments to Congress, to the President's office that
the economy would be better off without regulation, this was the "scientific rationale for it"
and led to the very unstable situation of the last economic crisis.
And indeed there's still a very dangerous and unstable situation in the world economy
because -- well, I'm not an economist. I'm not gonna pontificate about the problems in
the economy, but one could see how the idea of timelessness gave false comfort to an unsuccessful
scientific theory in the realm of economics.