" Since he held no troublesome parchment office, he was unlikely to be called upon to speak in chapter upon the various businesses of the house, and when the matter in hand was dull into the bargain it was his habit to employ the time to good account by sleeping, which from long usage he could do bolt upright and undetected in his shadowy corner. He had a sixth sense which alerted him at need, and brought him awake instantly and plausibly. He had even been known to answer a question pat, when it was certain he had been asleep when it was put to him. "

― Ellis Peters , A Morbid Taste for Bones (Chronicles of Brother Cadfael, #1)