The commenters here seem to have missed what I thought was Cal's point: What you know matters more than what you do, because what you can do is limited by what you know. Learning new techniques is important because it expands the arena of what you can do.
I think that is a given: Once you've done something, you intrinsically know how to do it.
More interestingly, to what degree does our knowledge play on our ability to see new ideas? Do our brains ignore the seemingly impossible because it seems impossible? Could someone have imagined Facebook before computers and the internet were invented, for example? Do the ideas come first, and then one set out to figure out how to make it work, like as it appears to happen in science fiction? Or are those ideas already based on working knowledge of what is reasonably possible with not-so-far-off technology?
The entire point seems to be "you must know how to do something before you do it". Academics seem to revel in stating the obvious in a formal tone with big words.
That's really a chicken-egg problem, no? We learn by doing (as children), and knowledge is better stored in our brains if it's supplemented with "doing".
