In his talk Inventing on Principle, Bret Victor sets the scene by explaining his own guiding principle, that "creators need an immediate connection with what they create." The interactive demonstrations in his talk are very impressive. You look at them and think "Why isn't my interaction with the computer like that? Why am I still struggling, still working by remote control?" The difference between his demos and the way we usually work is as dramatic as the difference between batch-processing and time-sharing.
"When you make a decision," says Victor, "you need to see the effect
of that immediately — there can't be any delay, can't be anything
hidden." The demos are lovely, and it's certainly nice to get rapid
feedback, but "need"? Do we really need it?
We can find a pretty clear answer to that question if we turn
around and consult the paper Conditions for Intuitive Expertise:
A Failure to Disagree by psychologists Daniel Kahneman and Gary Klein
(American Psychologist, Vol 64(6), Sep 2009, pp515-526).
years, Kahneman and Klein have been the central figures in two opposed
camps of psychologists studying human expertise. Kahneman, in the
"heuristics and biases" camp, enjoyed demonstrating that human
intuition is often flawed and that experts can often be
overconfident about their decisions. Klein, in the "naturalistic
decision making" camp, enjoyed celebrating the uncanny ability of
experts to make good decisions in complex situations and under time
For example, Klein found from many interviews with firefighters that
rather than thinking of a number of options (or even just two) and
deciding between them, they usually only thought of one option — the
right one — and then quickly checked that it was appropriate for the
current situation. Their intuition really works. On the other hand,
"experts" in other fields don't seem so capable. Unfortunately, their
intuitions are still compelling and feel to them just as just as
correct as the firefighters' — but this feeling is
deceptive. For example, in
Michael Lewis describes how
baseball scouts fail time and again to choose the most effective
players because they fall for the "representativeness" heuristic:
they pick good lookers, rather than good performers.
Was it possible to reconcile these two conflicting points of view?
Kahneman and Klein decided to try settle their differences by
writing a paper together. Both camps were clearly right some of the
time — experts are of course sometimes accurate and sometimes wide
of the mark. But was there a pattern? "What are the activities," they
asked, "in which skilled intuitive judgement develops with experience?
And what are the activities in which experience is more likely to
produce overconfidence than genuine skill?"
In the end, the two psychologists demonstrated "a failure to
disagree". Reconciling the evidence from each camp, they describe in
their paper the precise conditions for skilled intuition to
develop. Firstly, there must be a "high-validity" environment, or in
other words there must be cues in the observable environment which
indicate the true nature of the current situation. For example,
firefighters and paediatric nurses inhabit high-validity environments,
because they can perceive early indications that a building will
collapse or that a baby will suffer from an infection. They will often
be unaware of the precise cues which guide their intuitive decisions,
but the cues are there all the same.
Secondly, people must have an opportunity to learn the cues and to get
feedback when they are right and when they are wrong. But humans are
pretty good at this, provided they are in a high-validity
environment. As Kahneman and Klein note: "Where simple and valid cues
exist, humans will find them if they are given sufficient experience
and enough rapid feedback to do so". But the key for us here is the
feedback: to build skilled intuition this must be "both rapid and
So, let's now come back to Brett Victor and his principle of rapid
feedback. Do we need it? Computer programming certainly forms a
high-validity environment. We should be able to become intuitive
experts, but as you can now see, that depends critically on whether
the feedback we get is "both rapid and unequivocal". In most
programming environments nowadays the feedback is neither.
(I leave it as an exercise for the reader to work out whether a
kitchen is a high-validity environment. The point Victor was making
about rapid feedback seems to have been missed by so many people that
he felt it necessary to construct a web-page explaining it all over
again. That account is certainly worth reading too, and you can find it here: