David Hume, and that of the British empiricist tradition, that belief arises
from custom, as they assumed that we learn generalizations solely from
experience and empirical observations, it was shown from studies of infant
behavior that we come equipped with mental machinery that causes
us to selectively generalize from experiences (i.e., to selectively acquire inductive
learning in some domains but remain skeptical in others). By
doing so, we are not learning from a mere thousand days, but benefiting,
thanks to evolution, from the learning of our ancestors—which found its
way into our biology.
CONFIRMATION SHMONFIRMATION! 61
Back to Mediocristan
And we may have learned things wrong from our ancestors. I speculate
here that we probably inherited the instincts adequate for survival in the
East African Great Lakes region where we presumably hail from, but these
instincts are certainly not well adapted to the present, post-alphabet, intensely
informational, and statistically complex environment.
Indeed our environment is a bit more complex than we (and our institutions)
seem to realize. How? The modern world, being Extremistan, is
dominated by rare—very rare—events. It can deliver a Black Swan after
thousands and thousands of white ones, so we need to withhold judgment
for longer than we are inclined to. As I said in Chapter 3, it is impossible—
biologically impossible—to run into a human several hundred miles tall,
so our intuitions rule these events out. But the sales of a book or the magnitude
of social events do not follow such strictures. It takes a lot more
than a thousand days to accept that a writer is ungifted, a market will not
crash, a war will not happen, a project is hopeless, a country is "our ally,"
a company will not go bust, a brokerage-house security analyst is not a
charlatan, or a neighbor will not attack us. In the distant past, humans
could make inferences far more accurately and quickly.
Furthermore, the sources of Black Swans today have multiplied beyond
measurability. * In the primitive environment they were limited
to newly encountered wild animals, new enemies, and abrupt weather
changes. These events were repeatable enough for us to have built an innate
fear of them. This instinct to make inferences rather quickly, and to
"tunnel" (i.e., focus on a small number of sources of uncertainty, or causes
of known Black Swans) remains rather ingrained in us. This instinct, in a
word, is our predicament.
* Clearly, weather-related and geodesic events (such as tornadoes and earthquakes)
have not changed much over the past millennium, but what have changed are the
socioeconomic consequences of such occurrences. Today, an earthquake or hurricane
commands more and more severe economic consequences than it did in the
past because of the interlocking relationships between economic entities and the
intensification of the "network effects" that we will discuss in Part Three. Matters
that used to have mild effects now command a high impact. Tokyo's 1923 earthquake
caused a drop of about a third in Japan's GNP. Extrapolating from the
tragedy of Kobe in 1994, we can easily infer that the consequences of another such
earthquake in Tokyo would be far costlier than that of its predecessor.
Chapter Six
THE NARRATIVE FALLACY
The cause of the because—How to split a brain—Effective methods of pointing
at the ceiling—Dopamine will help you win—I will stop riding motorcycles
(but not today)—Both empirical and psychologist? Since when?
ON THE CAUSES OF MY REJECTION OF CAUSES
During the fall of 2 0 0 4 , 1 attended a conference on aesthetics and science
in Rome, perhaps the best possible location for such a meeting since aesthetics
permeates everything there, down to one's personal behavior and
tone of voice. At lunch, a prominent professor from a university in southern
Italy greeted me with extreme enthusiasm. I had listened earlier that
morning to his impassioned presentation; he was so charismatic, so con-,
vinced, and so convincing that, although I could not understand much of
what he said, I found myself fully agreeing with everything. I could only
make out a sentence here and there, since my knowledge of Italian worked
better in cocktail parties than in intellectual and scholarly venues. At some
point during his speech, he turned all red with anger-—thus convincing me
(and the audience) that he was definitely right.
He assailed me during lunch to congratulate me for showing the effects
of those causal links that are more prevalent in the human mind than in
reality. The conversation got so animated that we stood together near the
THE NARRATIVE FALLACY 6 3
buffet table, blocking the other delegates from getting close to the food.
He was speaking accented French (with his hands), I was answering in
primitive Italian (with my hands), and we were so vivacious that the other
guests were afraid to interrupt a conversation of such importance and animation.
He was emphatic about my previous book on randomness, a sort
of angry trader's reaction against blindness to luck in life and in the markets,
which had been published there under the musical title Giocati dal
caso. I had been lucky to have a translator who knew almost more about
the topic than I did, and the book found a small following among Italian
intellectuals. "I am a huge fan of your ideas, but I feel slighted. These are
truly mine too, and you wrote the book that I (almost) planned to write,"
he said. "You are a lucky man; you presented in such a comprehensive
way the effect of chance on society and the overestimation of cause and effect.
You show how stupid we are to systematically try to explain skills."
He stopped, then added, in a calmer tone: "But, mon cher ami, let me
tell you quelque chose [uttered very slowly, with his thumb hitting his
index and middle fingers]: had you grown up in a Protestant society where
people are told that efforts are linked to rewards and individual responsibility
is emphasized, you would never have seen the world in such a manner.
You were able to see luck and separate cause and effect because of
your Eastern Orthodox Mediterranean heritage." He was using the
French à cause. And he was so convincing that, for a minute, I agreed with
his interpretation.
We like stories, we like to summarize, and we like to simplify, i.e., to reduce
the dimension of matters. The first of the problems of human nature
that we examine in this section, the one just illustrated above, is what I call
the narrative fallacy. (It is actually a fraud, but, to be more polite, I will
call it a fallacy.) The fallacy is associated with our vulnerability to overinterpretation
and our predilection for compact stories over raw truths. It
severely distorts our mental representation of the world; it is particularly
acute when it comes to the rare event.
Notice how my thoughtful Italian fellow traveler shared my militancy
against overinterpretation and against the overestimation of cause, yet
was unable to see me and my work without a reason, a cause, tagged to
both, as anything other than part of a story. He had to invent a cause. Furthermore,
he was not aware of his having fallen into the causation trap,
nor was I immediately aware of it myself.
The narrative fallacy addresses our limited ability to look at sequences
6 4 UMBERTO E C O ' S A N T I U B R A RY
of facts without weaving an explanation into them, or, equivalently, forcing
a logical link, an arrow of relationship, upon them. Explanations bind
facts together. They make them all the more easily remembered; they help
them make more sense. Where this propensity can go wrong is when it increases
our impression of understanding.
This chapter will cover, just like the preceding one, a single problem, but
seemingly in different disciplines. The problem of narrativity, although extensively
studied in one of its versions by psychologists, is not so "psychological":
something about the way disciplines are designed masks the
point that it is more generally a problem of information. While narrativity
comes from an ingrained biological need to reduce dimensionality, robots
would be prone to the same process of reduction. Information wants to be
reduced.
To help the reader locate himself: in studying the problem of induction
in the previous chapter, we examined what could be inferred about the unseen,
what lies outside our information set. Here, we look at the seen,
what lies within the information set, and we examine the distortions in the
act of processing it. There is plenty to say on this topic, but the angle I take
concerns narrativity's simplification of the world around us and its effects
on our perception o￡ the Black Swan and wild uncertainty.
SPLITTING BRAINS
Ferreting out antilogies is an exhilarating activity. For a few months, you
experience the titillating sensation that you've just entered a new world.
After that, the novelty fades, and your thinking returns to business as
usual. The world is dull again until you find another subject to be excited
about (or manage to put another hotshot in a state of total rage).
For me, one such antilogic came with the discovery—thanks to the literature
on cognition—that, counter to what everyone believes, not theorizing
is an act—that theorizing can correspond to the absence of willed
activity, the "default" option. It takes considerable effort to see facts (and
remember them) while withholding judgment and resisting explanations.
And this theorizing disease is rarely under our control: it is largely
anatomical, part of our biology, so fighting it requires fighting one's own
self. So the ancient skeptics' precepts to withhold judgment go against our
nature. Talk is cheap, a problem with advice-giving philosophy we will see
in Chapter 13.
THE NARRATIVE FALLACY 6 5
Try to be a true skeptic with respect to your interpretations and you
will be worn out in no time. You will also be humiliated for resisting to
theorize. (There are tricks to achieving true skepticism; but you have to go
through the back door rather than engage in a frontal attack on yourself.)
Even from an anatomical perspective, it is impossible for our brain to see
anything in raw form without some interpretation. We may not even always
be conscious of it.
Post hoc rationalization. In an experiment, psychologists asked women
to select from among twelve pairs of nylon stockings the ones they preferred.
The researchers then asked the women their reasons for their
choices. Texture, "feel," and color featured among the selected reasons. All
the pairs of stockings were, in fact, identical. The women supplied backfit,
post hoc explanations. Does this suggest that we are better at explaining
than at understanding? Let us see.
A series of famous experiments on split-brain patients gives us convincing
physical—that is, biological—evidence of the automatic aspect of
the act of interpretation. There appears, to be a sense-making organ in
us—though it may not be easy to zoom in on it with any precision. Let us
see how it is detected.
Split-brain patients have no connection between the left and the right
sides of their brains, which prevents information from being shared between
the two cerebral hemispheres. These patients are jewels, rare and invaluable
for researchers. You literally have two different persons, and you can
communicate with each one of them separately; the differences between
the two individuals give you some indication about the specialization of
each of the hemispheres. This splitting is usually the result of surgery to
remedy more serious conditions like severe epilepsy; no, scientists in Western
countries (and most Eastern ones) are no longer allowed to cut human
brains in half, even if it is for the pursuit of knowledge and wisdom.
Now, say that you induced such a person to perform an act—raise his
finger, laugh, or grab a shovel—in order to ascertain how he ascribes a
reason to his act (when in fact you know that there is no reason for it other
than your inducing it). If you ask the right hemisphere, here isolated from
the left side, to perform the action, then ask the other hemisphere for an
explanation, the patient will invariably offer some interpretation: "I was
pointing at the ceiling in order to . . . ," "I saw something interesting on
the wall," or, if you ask this author, I will offer my usual "because I
am originally from the Greek Orthodox village of Amioun, northern
Lebanon," et cetera.
6 6 UMBERTO E C O ' S A N T I L I B R A RY
* The word the is written twice.
Now, if you do the opposite, namely instruct the isolated left hemisphere
of a right-handed person to perform an act and ask the right hemisphere
for the reasons, you will be plainly told, "I don't know." Note that
the left hemisphere is where language and deduction generally reside. I
warn the reader hungry for "science" against attempts to build a neural
map: all I'm trying to show is the biological basis of this tendency toward
causality, not its precise location. There are reasons for us to be suspicious
of these "right brain/left brain" distinctions and subsequent pop-science
generalizations about personality. Indeed, the idea that the left brain controls
language may not be so accurate: the left brain seems more precisely
to be where pattern recognition resides, and it may control language only
insofar as language has a pattern-recognition attribute. Another difference
between the hemispheres is that the right brain deals with novelty. It tends
to see series of facts (the particular, or the trees) while the left one perceives
the patterns, the gestalt (the general, or the forest).
To see an illustration of our biological dependence on a story, consider
the following experiment. First, read this:
A B I R D I N T H E
T H E H A N D I S W O R T H
T W O I N T H E B U S H
Do you see anything unusual? Try again.*
The Sydney-based brain scientist Alan Snyder (who has a Philadelphia
