In changing your view, you must balance the amount of change involved against the improvement in explanatory coherence resulting from the change. Even if change and improvement in coherence are measured by simply counting, there can be no general requirement that the number of modified items (added or subtracted) be no greater than the number of new explanatory and implications links. The relation between conservatism and coherence is mroe complex than that.

The simplicity of a hypothesis for a person cannot be measured by the simplicity of the person's representation of that hypothesis (for example, the number of symbols used), because any hypothesis can be represented with a single symbol. A better measure of simplicity is the ease with which the hypothesis can be used to account for actual and foreseeable data. But it is also important to allow for different ways in which data might be represented. W e suggest that the relevant ways of representing data are those ways in which the person is interested, i.e., those representations that most directly help to answer questions the person wants to answer. In particular, we suggest that the simplicity of a hypothesis for a person is determined by the shortness of the connection between that hypothesis and the data that interest the person, as measured by the number of intermediate steps he or she needs to appreciate in order to appreciate the complete connection.