With almost all of the world's codified knowledge at your fingertips, why should you spend increasingly scarce attention loading up your own mind just in case you may some day need this particular fact or concept? Far better, one might argue, to access efficiently what you need, when you need it. This depends, of course, on building up a sufficient internalized structure of concepts to be able to link with the online store of knowledge. How to teach this is perhaps the greatest challenge and opportunity facing educators in the 21st century.