I (your regular News writer, O’Leary) am enjoying a week off to write something else, but noted that some commenters at How clever is that cockatoo? (and elsewhere?) wanted an ID definition of intelligence.
Here is the conventional definition with which I am familiar, and I think most ID theorists would accept it:
The Latin verb “intellego” (inter + lego) means “I choose between.” Intelligence, so defined, means the ability to choose one solution to a problem where other, less productive, ones are available.
An intelligent dog, observing humans raising the latch on a grooming shop cage’s door, may realize that he could raise the latch on his cage himself, using his jaw or paw. (I have seen a dog figure this out, unassisted.) A less intelligent dog would choose a less successful strategy—perhaps, just whine and bark for a human to come and do it (in a situation where no human has any intention of doing it until the groomer is ready for the dog). 😉
Choosing the correct solution is the way intelligence creates information. The more intelligent dog now has information about how to free himself from the cage. The less intelligent dog does not.
A human can frustrate even an intelligent dog’s escape efforts by transferring him to a different cage, perhaps one where 1) he cannot see exactly what the human is doing; or 2) fingers are needed to work the mechanism; or 3) a punched-in numerical code opens the door.
What the humans have done in this case is moved the search space for solutions beyond the physical and/or mental capacities of the dog.
Animals differ both individually and by species in intelligence in this sense. There does not appear to be a strict hierarchy of intelligence. Birds species, in particular, seem to vary widely in their ability to choose a successful strategy from alternatives, as opposed to simply following some sort of imprint, for good or ill.
Note that “intelligence” in this sense is quite distinct from “wisdom” or “insight” or other similar qualities.