LOGICA DOCENS AND LOGICA UTENS

The king turned pale, and shut his note-book hastily. "Consider your verdict," he said to the jury in a low trembling voice.

"There's more evidence to come yet, please your Majesty," said the White Rabbit, jumping up in a great hurry: "this paper has just been picked up."

"What is in it?" said the Queen.

"I haven't opened it yet," said the White Rabbit: "in fact, there's nothing written on the outside." He unfolded the paper as he spoke, and added "It isn't a letter, after all: it's a set of verses."

"Are they in the prisoner's handwriting?" asked another of the jurymen.

"No, they're not," said the White Rabbit, "and that's the queerest thing about it." (The jury all looked puzzled.)

He must have imitated somebody else's hand," said the King. (The jury all brightened up again.)

"Please your Majesty," said the Knave. "I didn't write it, and they can't prove that I did: there's no name signed at the end."

"If you didn't sign it," said the King, "that only makes the matter worse. You must have meant some mischief, or else you'd have signed your name like an honest man."

There was a general clapping of hands at this: it was the first really clever thing that the King had said that day�

from Alice in Wonderland

by Lewis Carroll

The King's inferences are somewhat loopy--to say the least. The King has based these inferences upon a set of assumptions about the way that he already believes that matters should turn out in this case. The King began the trial with a clear idea that the Knave is guilty of something--so he explained away every fact to validate his pre-existing belief. Though we are none of us as loopy as the King, we all enter situations with expectations for matters to be, or to proceed, in certain ways. One big difference among individuals is how someone deals with a situation that does not meet prior expectations. Many people are like the King. They adjust whatever data comes along to match their prior expectations--by selecting in what seems to fit their preconceived belief and excluding or

explaining away what does not. Sometimes, however, it is not possible to exclude or explain away data. Sometimes we find ourselves sliding down a rabbit-hole and we have to figure out how to make sense of things all over again. The way we make sense of things is by making inferences in whatever way we are most inclined to infer. The term "logica docens" refers to the formation and application of inferences that a person has learned to make by means of training and practice. The term "logica utens" means "logic in use," and refers to the instinctive habits of mind by which we make most of the inferences of our daily lives. Logica docens provides the norms (standards) by which reasoning should be done during a particular phase of reasoning. Logica utens refers to the way that reasoning is instinctively performed, regardless of what is best for a reasoning phase....