Usually, AI isn’t whether a computer or program can “learn”, but whether or not it can “think”. The Turing test is what’s frequently referred to in those regards, (as already mentioned by flatfoot).

http://www.britannica.com/EBchecked/topic/609757/Turing-test

Although I’ve read all of the posts, it was done in “real time” so forgive me if I mention something already stated.

Since Peter has already given a definitive answer to the original question, we seem to be discussing AI in general.

Most of what I’ve read about AI has dealt with computer gaming and refers to how well your computer “opponent” responds to numerous different attacks you make against your opponent at a given point in the game. If it always does the same thing regardless of your attack, the AI is bad. If it varies and responds well to different types of attacks, the AI is good.

The ONLY computer program I’ve ever used that could “learn” was a PC game called Black & White. Here’s a short quote about it on an instructional site for game developers using this game for reference:

Quote:

Black and White – Learning AI
Description: Black and White is a game in which you play a god sent to a planet to do good or evil. The path you choose shapes the land and the inhabitants. You are given a creature of your choosing to act as your visible avatar in the world. But you have limited control over this creature and they must be controlled somewhat like a pet animal.
System:
In Black and White you are given a creature which you can train to work for you. You can teach them to play and work but the use of a praise/ punishment system. When you show the creature something an action, you can then access the interface for the praise/ punishment. Then you can either encourage the action or discourage it by either beating the creature or petting it.



http://instructinator.com/marking/?p=130

The game won a lot of awards, primarily for the AI. The AI was so good, it was borderline creepy! (Highly recommended if you like strategy games). Your “creature” actually develops a personality based on your input and will exhibit different emotional and physical responses to what happens in the game.

So whether AI means to “think” or to “learn” remains debatable, but we’re obviously just on the cusp of both. We do live in interesting times.

Bob
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http://soundcloud.com/bobcflatpicke/music-in-the-mountains