Similar, yet different

I've always been captivated by this phrase, and for some reason, it really rings true in my exprerience with software development. It seems like I run into two kinds of people. The first kind seem to think that any innovation is really exactly the same as what they were doing 20 years ago. This is usually said in a grumbling tone - "Web based apps is nothing but a fancy 3270 terminal stream. We were doing thie same thing 30 years ago in CICS". The second kind is usually the guys 3-4 years out of school that are completely on the other side of the spectrum. This is usually said in a haughty, condescending tone - "Virtual Machines are totally revolutionary. These guys just don't get it."

It seems like both kinds of people suffer from the ability to see the truth is somewhere in the middle. Very few things are truly created ex nihilo, and therefore the ability to relate something new to lessons and mistakes that were learned from the past is very powerful. However, dismissing new things by only noting the similarity to something already out there and not seeing the differences is just as bad.