Martin Plessner suggests that a translator of the "Picatrix" established a medieval definition of scientific experiment by changing a passage in the Hebrew translation of the Arabic original, establishing a theoretical basis for the experimental method: "the invention of an hypothesis in order to explain a certain natural process, then the arranging of conditions under which that process may intentionally be brought about in accordance with the hypothesis, and finally, the justification or refutation of the hypothesis, depending on the outcome of the experiment".