Managing the semantic gap is a key criterion to managing knowledge dissemination throughout the corporation. Since knowledge is personal, software is required that can continually measure the distance to the user's semantic horizon. That way the software can bring information into play that stretches the user's horizons without breaking the boundaries. This will optimize learning productivity and encourage repeat behavior.

This is an essential point. Learning is all about growing context from where you are--your current context--in the intended direction. If users need to switch context to get answers, they lose too much associative material, forcing them to bridge the gap between where they are and where the context of the answer is. This bridging of the gap is extremely unproductive.

A simple example
Let's take a familiar example to drive the point home. Say you're in the kitchen where the telephone is and you need to call a number. However, the telephone book is in the front hall, chained to a desk so that it's always where you expect it to be. You go to the hall, open the book, and find the phone number you need. Then, on your way back to the kitchen, you're interrupted by one of your children who must have an answer to their question immediately (immediacy seems to be characteristic of the Nintendo Generation).

You respond and continue on your way, but once you get to the kitchen, you forget the phone number. In fact, if you're like most of us, you forget why you left the kitchen in the first place.

Context switching
This is called "context switching." It's hard to re-contextualize as you switch from one context to another. It's much more productive to grow context from where you are incrementally, where the user is in control of how much new context is layered around their existing knowledge. This is what learning trees are all about. Forced context-switching places a significant strain on corporate productivity. That's why time blocking and task prioritization is so key and so effective in time management techniques.

We all have coping mechanisms to mitigate the impact on context switching. Let's replay the above example to show the ways we learn to cope with context switching. Because you've learned from experience that you'll always be interrupted when you're trying to bridge context, you develop a number of context-bridging techniques to anchor context. You try repeating the phone number in your head as you walk from the hall to the kitchen. But if there's more than one non-related question to respond to on the way, you often can't recall the number you were repeating. You might find the best way is to write the phone number on the palm of your hand in ink (perhaps the precursor to the Palm computer!) Or, as the old adage goes: you "tie a string around your finger."

Now when you arrive back in the kitchen, you recover your context by looking at your hand. Not only do you remember why you left the kitchen in the first place, but you also have the phone number.