 A decision to accept or reject a scientific statement (for instance an hypothesis) is in practice always subject to the possibility of error. The chance of such an error is often called the inductive risk (Hempel 1965, 92). There are two major types of errors. The first of these consists in concluding that there is a phenomenon or an effect when in fact there is none. This is called an error of type I (false positive). The second consists in missing an existing phenomenon or effect. This is called an error of type II (false negative). In the internal dealings of science, errors of type I are in general regarded as more problematic than those of type II. The common scientific standards of statistical significance substantially reduce the risk of type I errors but do not protect against type II errors (Shrader-Frechette 2008; John 2017).