Is There a Bias in Subtraction?

People are more likely to rely on their default mental settings if they have other things to think about. Astrider bikes give two-year-olds the ability to walk and pedal without training wheels, for example. People will quibble with this example, but the point is that there was all this innovation in the kid's bike market,. whether its training wheels, the little cabooses on the back of a bike, fetter tires, fetter tubes - nobody thought to take ay the petals from them.