"There are a lot of complex assumptions necessary to do adjustments, and reasonable people will disagree about the best way to proceed, " she says.

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And it cited the Scottish government's own assumptions that road pricing would be necessary.

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For example, if robotic devices can restore sight or mobility, it may be necessary to redefine what disability is which might, in turn, conflict with the assumptions on which existing disability-rights legislation is based.

ECONOMIST: Monitor