{ Installment 9 in Ivan Illich’s Energy and Equity series. }

Dominant versus subsidiary motors

People are born almost equally mobile. Their natural ability speaks for the personal liberty of each one to go wherever he or she wants to go. Citizens of a society founded on the notion of equity will demand the protection of this right against any abridgment. It should be irrelevant to them by what means the exercise of personal mobility is denied, whether by imprisonment, bondage to an estate, revocation of a passport, or enclosure within an environment that encroaches on a person’s native ability to move in order to make him a consumer of transport. This inalienable right of free movement does not lapse just because most of our contemporaries have strapped themselves into ideological seat belts. Man’s natural capacity for transit emerges as the only yardstick by which to measure the contribution transport can make to traffic: there is only so much transport that traffic can bear. It remains to be outlined how we can distinguish those forms of transport that cripple the power to move from those that enhance it.

{ Installment 8 of Ivan Illich’s Energy and Equity series }

Degrees of self-powered mobility

A century ago, the ball-bearing was invented. It reduced the coefficient of friction by a factor of a thousand. By applying a well-calibrated ball-bearing between two Neolithic millstones, a man could now grind in a day what took his ancestors a week. The ball-bearing also made possible the bicycle, allowing the wheel-probably the last of the great Neolithic inventions-finally to become useful for self-powered mobility.

Man, unaided by any tool, gets around quite efficiently. He carries one gram of his weight over a kilometer in ten minutes by expending 0.75 calories. Man on his feet is thermodynamically more efficient than any motorized vehicle and most animals. For his weight, he performs more work in locomotion than rats or oxen, less than horses or sturgeon. At this rate of efficiency man settled the world and made its history. At this rate peasant societies spend less than 5 per cent and nomads less than 8 per cent of their respective social time budgets outside the home or the encampment.