Nevertheless we need logic, this terrible power, in order to communicate thoughts and perceptions and even in order to think and perceive, for we think with words, we perceive with forms. To think is to converse with oneself; and speech is social, and social are thought and logic. But may they not perhaps possess a content, an individual matter, incommunicable and untranslatable? And may not this be the source of their power? The truth is that man, the prisoner of logic, without which he cannot think, has always sought to make logic subservient to his desires, and principally to his fundamental desire. He has always sought to hold fast to logic, and especially in the Middle Ages, in the interests of theology and jurisprudence, both of which based themselves on what was established by authority. It was not until very much later that logic propounded the problem of knowledge, the problem of its own validity, the scrutiny of the metalogical foundations. "The Western theology," Dean Stanley wrote, "is essentially logical in form and based on law. The Eastern theology is rhetorical in form and based on philosophy. The Latin divine succeeded to the Roman advocate. The Oriental divine succeeded to the Grecian sophist."[28] And all the laboured arguments in support of our hunger of immortality, which pretend to be grounded on reason or logic, are merely advocacy and sophistry. The property and characteristic of advocacy is, in effect, to make use of logic in the interests of a thesis that is to be defended, while, on the other hand, the strictly scientific method proceeds from the facts, the data, presented to us by reality, in order that it may arrive, or not arrive, as the case may be, at a certain conclusion. What is important is to define the problem clearly, whence it follows that progress consists not seldom in undoing what has been done. Advocacy always supposes a _petitio principii_, and its arguments are _ad probandum_. And theology that pretends to be rational is nothing but advocacy.