Quapropter bene cum superis de rebus habenda nobis est ratio, solis lunaeque meatus qua fiant ratione, et qua vi quaeque gerantur in terris, tum cum primis ratione sagaci unde anima atque animi constet natura videndum, et quae res nobis vigilantibus obvia mentes terrificet morbo adfectis somnoque sepultis, cernere uti videamur eos audireque coram, morte obita quorum tellus amplectitur ossa.
Therefore, it is necessary not only to establish correct principles regarding celestial matters such as the movements of the sun and the moon, as well as the powers at work on earth, but also to thoroughly examine with sharp reasoning the composition of the spirit and the nature of the mind. We must also investigate that which confronts us and causes fear in our minds while we suffer from illness or sleep, such that we seem to see and hear those who have died and now lie at rest within the earth's embrace.