 The claim that Grosseteste developed an account of experimental method in science puts great weight on the aforementioned passage in which Grosseteste describes a controlled experiment to see whether scammony causes the discharge of red bile.  There can be little doubt that Grosseteste does indeed have in mind the idea of a controlled experiment. The question, however, is whether Grosseteste makes the notion of controlled experiment part of a general account of a scientific method for arriving at the principles of demonstrative science. The evidence that he does so is not strong. The discussion of scammony is the only reference to controlled experiment in his writings, and when Grosseteste refers back to this discussion later in the commentary as explaining how we come to acquire experiential principles, the notion of controlled experiment is sometimes inapplicable—as for example, regarding our knowledge of the cause of an eclipse. Moreover, Grosseteste is quite prepared to grant that in some cases we can know causal connections after only a single perception (see Marrone 1986).  On balance, we may say that Grosseteste did employ the notion of controlled experiment and related it to demonstrative science, but he hardly set it up as the method by which such knowledge is to be obtained; it is one among many ways of arriving at such knowledge and is not accorded the emphasis it has been given in scholarly commentary.