Ladri di biciclette
Post 373
Tags: Whee, Bicycle, Sella, Duchamp, Picasso, Castiglioni, Toro
Marcel Duchamp, Bicycle Wheel, 1913
Pablo Picasso, Testa di Toro, 1943
Achille Castiglioni, Sella, 1971
Marcel Duchamp, Bicycle Wheel, 1913 | Pablo Picasso, Testa di Toro, 1943 | Achille Castiglioni, Sella, 1971
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Man on a bicycle can go three or four times faster than the pedestrian, but uses five times less energy in the process. He carries one gram of his weight over a kilometer of flat road at an expense of only 0.15 calories. The bicycle is the perfect transducer to match man's metabolic energy to the impedance of locomotion. Equipped with this tool, man outstrips the efficiency of not only all machines but all other animals as well.

A century ago, the ball-bearingwas invented. It reduced the coefficient of friction by a factor of athousand. By applying a well-calibrated ball-bearing between twoNeolithic millstones, a man could now grind in a day what took hisancestors a week. The ball-bearing also made possible the bicycle,allowing the wheel -- probably the last of the great Neolithicinventions -- finally to become useful for self-poweredmobility.

Man, unaided by any tool, gets around quiteefficiently. He carries one gram of his weight over a kilometer inten minutes by expending 0.75 calories. Man on his feet isthermodynamically more efficient than any motorized vehicle and mostanimals. For his weight, he performs more work in locomotion thanrats or oxen, less than horses or sturgeon. At this rate ofefficiency man settled the world and made its history. At this ratepeasant societies spend less than 5 per cent and nomads less than 8per cent of their respective social time budgets outside the home orthe encampment.

Man on a bicycle can go three or four timesfaster than the pedestrian, but uses five times less energy in theprocess. He carries one gram of his weight over a kilometer of flatroad at an expense of only 0.15 calories. The bicycle is the perfecttransducer to match man's metabolic energy to the impedance oflocomotion. Equipped with this tool, man outstrips the efficiency ofnot only all machines but all other animals as well.

The ball-bearing signaled a true crisis, a true politicalchoice. It created an option between more freedom in equity and morespeed. The bearing is an equally fundamental ingredient of two newtypes of locomotion, respectively symbolized by the bicycle and thecar. The bicycle lifted man's auto-mobility into a new order, beyondwhich progress is theoretically not possible. In contrast, theaccelerating individual capsule enabled societies to engage in aritual of progressively paralyzing speed.

Bicycles arenot only thermodynamically efficient, they are also cheap. With hismuch lower salary, the Chinese acquires his durable bicycle in afraction of the working hours an American devotes to the purchase ofhis obsolescent car. The cost of public utilities needed tofacilitate bicycle traffic versus the price of an infrastructuretailored to high speeds is proportionately even less than the pricedifferential of the vehicles used in the two systems. In the bicyclesystem, engineered roads are necessary only at certain points ofdense traffic, and people who live far from the surfaced path are notthereby automatically isolated as they would be if they depended oncars or trains. The bicycle has extended man's radius withoutshunting him onto roads he cannot walk. Where he cannot ride hisbike, he can usually push it.

The bicycle also useslittle space. Eighteen bikes can be parked in the place of one car,thirty of them can move along in the space devoured by a singleautomobile. It takes three lanes of a given size to move 40,000people across a bridge in one hour by using automated trains, four tomove them on buses, twelve to move them in their cars, and only twolanes for them to pedal across on bicycles. Of all these vehicles,only the bicycle really allows people to go from door to door withoutwalking. The cyclist can reach new destinations of his choice withouthis tool creating new locations from which he is barred.

Bicycleslet people move with greater speed without taking up significantamounts of scarce space, energy, or time. They can spend fewer hourson each mile and still travel more miles in a year. They can get thebenefit of technological breakthroughs without putting undue claimson the schedules, energy, or space of others. They become masters oftheir own movements without blocking those of their fellows. Theirnew tool creates only those demands which it can also satisfy. Everyincrease in motorized speed creates new demands on space and time.The use of the bicycle is self-limiting. It allows people to create anew relationship between their life-space and their life-time,between their territory and the pulse of their being, withoutdestroying their inherited balance. The advantages of modernself-powered traffic are obvious, and ignored. That better trafficruns faster is asserted, but never proved. Before they ask people topay for it, those who propose acceleration should try to display theevidence for their claim.

 

Ivan Illich -  Energy and Equity

 

 
 
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