Punctuated Equilibrium and the Validation of Macroevolutionary Theory 957
influential textbooks ever written, and a volume that, through decades and
numerous editions, bore on its title page the Leibnizian, Linnaean, and Darwinian
maxim: Natura non facit saltum. Boulding writes: "In the economy we certainly
find periods of relative stability, in which society is getting neither much richer nor
much poorer, but these periods of stability do seem to be punctuated by periods of
very rapid economic development. The transition from hunting-gathering societies
to agriculture at any particular locality seems to set off a period of rapid economic
growth. This transition was usually rather rapid and, it would seem, irreversible."
EXAMPLES FROM HUMAN INSTITUTIONS AND THEORIES ABOUT THE
NATURAL WORLD. If relatively prolonged periods of actively maintained
stability, followed by episodic transition to new positions of repose, mark the most
characteristic style of change across nature's scales, and if we have generally tried
to impose a gradualistic and progressivistic model of change upon this different
reality, then we must often face anomalies that engender confusion and frustration
in our personal efforts to improve our lives or to master some skill. To cite two
mundane examples from my own experience, I spent several, ultimately rather
fruitless years learning to play the piano. Whenever I tried to master a piece, I
would become intensely frustrated at my minimal progress for long periods, and
then exhilarated when everything "came together" so quickly, and I could finally
play the piece. I also liked to memorize long passages of poetry and great
literature, primarily Shakespeare and the Bible, an activity then practiced and
honored in the public primary and secondary schools of America. I would get
nowhere forever, or so it seemed— and then, one fine day, I would simply know
the entire passage.
Only years later—and perhaps serving as a spur to my later interest in
punctuated equilibrium—did I conceptualize the possibility that plateaus of
stagnation and bursts of achievement might express a standard pattern for human
learning, and that my previous frustration (at the long plateaus), and my
exhilaration (at the quick and rather mysterious bursts), might only have reflected a
false expectation that I had carried so long inside my head—the idea that every
day, in every way, I should be getting just a little bit better and better.
I don't know that explicit instruction in the higher probability of punctuational
change, and the consequent appeasement of frustration combined with a better
understanding of exhilaration, would improve the quality of our lives. (For all I
know, the frustration and exhilaration yield important psychological benefits that
outweigh their inadequate mapping of nature.) But I do suspect that a general
recognition of the principles of punctuational change— leading us to understand
that learning generally proceeds through plateaus of breakthroughs, and that
important changes in our lives occur more often by rapid transition than by gradual
accretion—might provide some distinct service in our struggles to fulfill the
ancient and honorable Socratic injunction: know thyself.
I also think that an explicit application of punctuational models to many