Sir, The ideas underlying Uber and Airbnb are not modern but about fundamental premodern concepts. Both are aimed at maximising private welfare at the expense of public welfare. Large cities have a collective interest to oppose them.

Uber is about promoting the use of the single car. City planners need to maximise use of public transport to allow large cities to operate as fluidly as possible, minimise air pollution and noise. Taxis are few and fares rather high precisely to make taxi journeys occasional only. The number of taxis needs to be carefully calibrated to complement public transport efficiently. In a confined space this is critical. The proliferation of private Uber cars runs contrary to that.

Airbnb risks unduly inflating the number of idle urban spaces for the sake of the occasional renter (“The Future of Cities”, Special Report, June 1). City planners aim to monitor the number of needed hotel beds to ensure that the use of urban space can be as productive as possible. Airbnb risks undermining the balance between living and hotel space and represents a source of critical co-ordination failure.

Premodern Luddites who opposed the power loom and other machinery are fundamentally different, as they tried to block technological change that aimed at advancing the private interests of employment.

Uber and Airbnb are anachronistic, old-fashioned ideas. In large cities, helping them does not make sense. Collective interests to guide adequate planning is needed. This should result in fewer cars and fewer idle urban spaces.

Ousmène Jacques Mandeng

London SW1, UK

Letter in response to this letter:

Uber has helped us cut car-related congestion / From Mel Glass

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