Otto Neurath argues in this periodi that not only for practical purposes of daily life but also in science decisions must be made even before evaluating all theoretically possible options, or even if thorough investigation ends up with equally probable alternatives, such as often appeared to be the case with the wave and particle theories of light from the 17th to the 19th centuries. In these cases Neurath has recommended the rationally-minded to decide on the basis of an "auxiliary motive". This is the way he labels procedures which do not add new content to the matter which is in question. Borrowing Kantian terminology, let me classify them as "formal". The purest auxiliary motives are simply tossing a coin or throwing dice, but also voting, instinctive action, or analogies can be applied in this way. They can help us choose between theories when the theories themselves seem equally supported by empirical data.