Diocles of Cnidos asserts in his ''Diatribae'', that through fear of the followers of Theodorus, and of the sophist Bion, who used to assail the philosophers, and shrank from no means of refuting them, Arcesilaus took precautions, in order to avoid trouble, by never appearing to suggest any dogma, but used to put forward the "suspense of judgement" as a protection, like the black juice which the cuttlefishes throw out.〔Eusebius, ''Praeparatio Evangelica'' 14.6〕