Current One-hour Lecture Topics
General Public, General Scientific audiences (it's mostly climate and
oceanography with some anthropology)|
Shocks and Instabilities:
Climate is like a drunk.
If left alone, it sits.
Forced to move, it staggers.
on stage now is a stunning example of how civilization must rescue itself.
It dwarfs the three big scientific alerts from the 1970s about global warming,
ozone loss, and acid rain. But until the 1990s, no one knew much about abrupt
climate change, those past occasions when the whole world flipped out of a
warm-and-wet climate like today’s into the alternate mode, which is like a
worldwide version of the Oklahoma Dust Bowl of the 1930s. There are
big alterations in only 3-5 years. A few centuries later, the drought
climate flips back into worldwide warm-and-wet, even more quickly. Unlike
greenhouse warmings, the big flips have happened every few thousand years on
average, though the most recent one was back before agriculture in 10,000 B.C.
The next flip may arrive sooner than otherwise, thanks to our current warming
trend. The northern extension of the Gulf Stream appears quite vulnerable
to global warming in four different ways. An early warning might be a
decline in this current. And according to two oceanographic studies
published this last year, this vulnerable ocean current has been
dramatically declining for the last 40-50 years, paralleling our global warming
and rising CO2.
The 2004 version of this talk, for the Adamson Annual Lecture on International
Studies, is here.
General Public, General Scientific audiences (it's mostly anthropology,
evolution, and psychology)
The Evolution of Human Minds:
The Ice Age Emergence of Higher Intellectual Functions
The suite of higher
intellectual functions includes syntax, multi-stage planning, structured
music, chains of logic, games with arbitrary rules, and our fondness for
discovering hidden patterns (the search for coherence). It's likely that
they share some neural machinery for handling structure and judging
coherence. But the archeological record suggests that they are late-comers
-- that the three-fold enlargement of the ape brain into the human brain was
complete about 150,000 years ago, but that they were intensely conservative,
doing little that Neanderthals didn’t do as well. The "behaviorally modern"
aspects were seldom seen before the Creative Explosion about 50,000 years
ago. So the big brain is not all about intellect. What happened to
reorganize the brain after 100,000 years at its present size, to make it
more creative and versatile, back during the middle of the most recent ice
version of this talk for WCBR 2005 is available as webbed
General Scientific and Cognitive Psychology audiences (it's mostly
neurobiology and evolutionary theory)
Cerebral Circuits for Creativity:
Bootstrapping Coherence using a Darwin Machine
The problem with creativity is not in putting together novel mixtures –
a little confusion may suffice – but in managing the incoherence. Things
often don’t hang together properly – as in our nighttime dreams, full
of people, places, and occasions that don’t fit together very well. What
sort of on-the-fly process does it take to convert such an incoherent
mix into a coherent compound, whether it be an on-target movement
program or a novel sentence to speak aloud? The bootstrapping of new
ideas works much like the immune response or the evolution of a new
animal species — except that the neocortical brain circuitry can turn
the Darwinian crank a lot faster, on the time scale of thought and
action. Few proposals achieve a Perfect Ten when judged against our
memories, but we can subconsciously try out variations, using this
Darwin Machine for copying competitions among cerebral codes.
Eventually, as quality improves, we become conscious of our new
invention. It's probably the source of our fascination with
discovering hidden order, with imagining how things hang together, seen
in getting the joke or doing science.
The version of this for Stanford University is
available as webbed slides.
Public and Cognitive Psychology audiences (it's mostly anthropology and
Planning ballistic movements
as an evolutionary setup for syntax
For slow movements, progress reports can update
the plan and correct an approximate intention. But for ballistic
movements that are over-and-done in 1/8 sec, the feedback is too
slow to correct the movement; you have to make the perfect plan
during get set.
We know that our ancestors were eating a lot of meat by about 1.8
million years ago. They had probably figured out how to bring down
big grazing animals, and with regularity. But accurate throwing (as
opposed to, say, the chimp’s fling of a branch) is a difficult task
for the brain. During “get set” one must improvise an
appropriate-to-the-target orchestration of a hundred muscles and
then execute the plan without feedback. While there are hundreds of
ways to throw that would hit a particular target, they are hidden
amidst millions of wrong answers, any one of which would cause
dinner to run away. Planning it right the first time, rather than
trying over and over, has real advantages. Just use the
ballistic movement planning circuits for other similar tasks in the
spare time. And what fits are the novel structured tasks of higher
intellectual function, such as syntax, contingent plans, polyphonic
music, getting the joke, and our search for how things all hang
together (seen in crossword puzzles and in doing science). Yes, some
of them “pay their own way” subsequently, but the free lunch
seems to be alive and well in the brain, where novel secondary uses
The Seattle University keynote slides are
To browse a
copy of one of my books, click on a cover for the link to amazon.com.
A Brief History of the Mind, 2004
A Brain for All Seasons
Lingua ex Machina
The Cerebral Code
How Brains Think
The River That
The Throwing Madonna