This
essay begins a series about the importance of walking in human evolution and
history.
Cogito,
ergo sum,
said Pascal, or someone. I think, therefore I am. In French it would be je
pense, donc je suis. But one French writer, an anthropologist named Pascal
Picq, has changed this a little. He says, je marche, donc je pense. I
walk, therefore I think. He has made the case that we are not just bipeds who
think, but we think because we are bipeds. He attributes the evolution of human
intelligence not just to the fact we are bipeds, but because we are
bipeds who can walk and run for long distances, with outstanding endurance not
found in other mammal species. Maybe this is obvious to you, but I’d never
thought of it until I read Picq’s book La Marche.
Picq
overviewed the history of scientific explanations for why humans walk upright.
This has always been somewhat of an enigma. Quadrupeds can run a lot faster
than we can. Anthropologists have come up with all kinds of advantages that
bipedalism conferred on our ancestors, such as being able to look out over the
vegetation to see either danger or opportunity, or to use our forelegs as arms
that can carry things such as food and kids and weapons. Long distance
migration is what evolution has favored in our species: even old people can
walk long distances unless they have health problems or are injured (I do it
nearly every day), and there are a lot more elderly marathon runners than
elderly speed sprinters.
While
these things are all true, Picq has added another: bipedalism has altered the
evolution of our minds. Bipedalism (as in Australopithecus) preceded
intelligence (as in Homo), and here are some reasons why.
Humans
are superb wanderers and have been so throughout our evolutionary history.
National Geographic writer Paul Salopek is retracing, on foot, the epic journey
of humankind from our African genesis to the end of the journey in South
America. Other mammals run faster, but do not migrate as far as humans have.
Starting about a hundred thousand years ago, prehistoric humans spread from
Africa to every continent except Antarctica. These migrations set up an
advantage for intelligence, because our ancestors had to decide whether to
migrate (that is, is migration worth the cost of leaving home), and then how to
get someplace and know that the new place was where we wanted to stay. This
required superb observation and memory of the environment and ability to
analyze opportunities. This was true on the short scale (we want to go this
way, but there is a river, and we have to figure out how to cross it, which may
involve turning around and going back the way we came) and the long scale (we
want to get to that hill, from which we can see into the distance and plan what
to do next, if anything). Homo sapiens was apparently better than this
than Homo neanderthalensis. Our intelligent ancestors also had to think
ahead about, and remember, the migration routes and habits of their prey.
Neanderthals killed mastodons; humans planned ahead about where the mastodons
would be before trying to kill them.
In
all these ways, our thinking evolved as a series of logical steps. That is, it
required reasoning ability. A primitive (or modern) philosopher or scientist
will try out ideas to see if they work, then come up with a backup plan if it
doesn’t. This, Picq speculates, uses a similar mental network to figuring out
where to go and how to get there on foot.
On
top of all that, walking and running makes us feel good and releases us from
stress. Picq said he got some of his best ideas while walking. I have the same
experience. And perhaps the best example is Charles Darwin, whose “walking
path” at Down House was where he got, and perfected, his major ideas. He did
not get them sitting at his desk. Many famous composers, as well as other
scholars, carried writing equipment with them. I have heard that Beethoven and
Dvořák wrote musical ideas as they walked (see a later essay on this topic).
Today, we have cell phones on which the thinking walker can record ideas.
According
to Picq, what science and philosophy needs more of is people who walk and
think, rather than sit at desks and read what other people have written.