Chapter 3 Tools for Analysis
Tutorial 7 Momentum and Path Dependency
Overview of Main Points
 Path Dependency explains how future technological decisions are
limited by previous technological decisions.
 Technological Momentum explains how technologies within a social
setting can develop a direction and velocity that is difficult to alter.
7.1 Introduction
In the last tutorial we saw how the emergence of a technology is dependent upon previous
technologies. We can expand this notion to say that technological and social contexts
generally determine the range of new technologies that can emerge. In addition, social
arrangements can help propel a technology forward, giving it strong technological
momentum.
7.2 Path Dependence
Given limited resources and inflexible social systems, society is often precluded from going
down a specific technological path. This is called path dependence.
We can begin by considering Figure 7.1. Initially we are forced to make a decision between
technology a and b. We cannot choose both – most of the time we do not have the resources
to follow two technological paths. As time goes by, our initial technological decision will
make technologies C and D available to us, while precluding the use of E and F.
Time
Tech. C
Technology A
Tech. D
OR
Tech. E
Technology B
Tech. F
Science, Technology and Society: A Tutorial for Engineers, Scientists and Business version 1.1 1997
Dr. Vincent G. Duffy IEEM and Dr. Robert Ferguson, SOSC The Hong Kong University of Science and Technology
Figure 7.1 Path Dependency
This is a simple illustration, but the idea of path dependency become more complex when we
consider how it interacts with human behavior. Technologies, of course, are not just physical
artifacts, but knowledge and techniques as well. We may find that while we have the option
of switching physical artifacts, we are unable to change our techniques or knowledge. Such is
the case of the QWERTY keyboard.
QWERTY refers to the arrangement of keys that one finds on most computer keyboards and
typewriters. When originally developed in the 19th century, the QWERTY arrangement was
an optimal match between human speed and the maximum speed that a typewriter could
operate without jamming. While typewriter designers could have used an arrangement that
allowed operators to type faster, the machine itself would have jammed. Therefore they
chose the QWERTY arrangement which is less than optimal, yet matched to the mechanical
technology of the time.
In the following decades, typewriter mechanisms improved, and new key and faster key
arrangements were also proposed. The QWERTY technique, however, had become a
standard technique. The technique prevented the acceptance of faster typing systems. Nearly
a hundred years after the development of typewriters, we have computers that use the
QWERTY keyboard!
7.3 Technological Momentum
Many times we have the opportunity to change our technology, or to make different
technological decisions, but we keep using the same technology anyway. In this case we say
that there is technological momentum.
We can first think about the ways in which technologies are chosen and used. Let’s consider
the following aspects of a technology.
– Organizations/Institutions
– Individual Practitioners
– Technology itself with systematized knowledge
We may call this list a technological culture. Built into this culture are traditions, ways of
thinking, biases, and interests that keep a technology moving. For example, a business that
sells “tech. A” will be interested in promoting that product, even if a “tech. B” sold by a
competitor is actually preferable. A government bureaucracy may be interested in continuing
a particular technology because the bureaucracy’s sole existence depends on that technology.
One quality of technological cultures, and one closely linked to the idea of path dependence,
is that technologies develop along previously defined trajectories unless and until deflected by
some powerful external force or some internal problem. Thus, technologies, because of their
technological cultures, have a momentum (implying that they have a vector -- a direction and
a velocity).
Science, Technology and Society: A Tutorial for Engineers, Scientists and Business version 1.1 1997
Dr. Vincent G. Duffy IEEM and Dr. Robert Ferguson, SOSC The Hong Kong University of Science and Technology
7.4 Example: Steel
Beginning in the early 20th century US steel companies expanded production capacity using
the open-hearth process. These companies became very good at operating the open-hearth
process. The open-hearth operations represented a significant investment of capital (money).
Since the 1960s, new Japanese and German technology emerged focusing on the electric
furnace. These furnaces could smelt smaller batches of steel, especially scrap. The US
companies would not switch to the newer technology, even when Japanese companies were
producing better steel at a lower price.
The US steel companies experienced a severe crisis, and many steel plants were forced to
close. Eventually new steel companies in the US began using the new electric furnace
technology, and they have been very successful.
Thus, a situation of technological momentum developed where the old US steel companies
could not (or would not) switch to the new technology because they were so committed to the
old (through their investments and their experience). It required a large external force (the
Japanese companies) to change the direction of the US steel industry.
7.5 Further Study
Hughes, Thomas P. Networks of Power: Electrification in Western Society, 1880-1930 (Baltimore: Johns
Hopkins University Press, 1983).
Rosenberg, Nathan. Inside the Black Box: Technology and Economics (London: Cambridge University Press,
1990).
Science, Technology and Society: A Tutorial for Engineers, Scientists and Business version 1.1 1997
Dr. Vincent G. Duffy IEEM and Dr. Robert Ferguson, SOSC The Hong Kong University of Science and Technology