PREDICTIONS – 10 Years Later - Santa Fe Institute

6. A HARD FACT OF LIFE
avoid wrong forecasts. 2 In this case such an analysis would have predicted
a poor future for cars.
Ironically, one of the early advantages attributed to the automobile
was its non-polluting operation. In large cities, removing horse excrement
from the streets was becoming a serious task, and projected
transport needs presented this problem as insurmountable. For this and
mostly for other more deeply rooted reasons, cars began replacing
horses rapidly and diffused in society as a popular means of transportation.
THE SUBSTITUTION OF CARS FOR HORSES IN PERSONAL TRANSPORTATION
As a percentage
of all "vehicles"
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
Horses
Cars
0%
1900 1905 1910 1915 1920 1925 1930
FIGURE 6.1 The data points represent percentages of the total number of transportation
units, namely, cars plus non-farming horses and mules. The S-curves
are fitted to the data points. The sum of respective ascending and descending
percentages equals 100% at any given time. ∗
∗ Adapted from Cesare Marchetti, “Infrastructures for Movement,” Technological Forecasting
and Social Change, vol. 32, no. 4 (1987): 373-93. Copyright 1986 by
Elsevier Science Publishing Co., Inc. Reprinted by permission of the publisher. Credit
for the original graph must be given to Nebosja Nakicenovic, “The Automobile Road to
Technological Change: Diffusion of the Automobile as a Process of Techological Substitution,”
Technological Forecasting and Social Change, vol. 29: 309–40.
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