''@jchyip In many things, the difference between the novice and the expert is the awareness and manipulation of negative space.''

Build a robot. Give it an arm to do this. Now give it an arm to do that. Then the OnsiteCustomer asks for the robot to carry serving trays, and toss light sabers. Add a couple more arms. Now the customer requests an arm to cast a fishing pole. 

Look at your robot, with arms sticking out all over it. 

There's not much room left. If you just try to stick this long new arm onto the base, same as you did the others, you will need to move some other arms, to give this one room to swing. And you must program the others, to keep them out of this one's way at casting time. And you might even find yourself making an arm or two shorter. 

Start the project again. (Your GoldOwner is the forgiving type - one JediMindTrick later...). This time around, you still add arms one at a time, but whenever you encounter two arms that do similar things you merge them together, and give them pluggable claws on the end. You might make arms that fold away better, and you can put hands on their elbows, too.

Now you have room for the fishing pole arm, and to spare. You have more DegreesOfFreedom for this new arm; more axes of rotation are available. 

You left space open for this new arm, by clearing out the other arms. You didn't predict this arm, or add it into the very first design. You simply made >those< arms already as efficient as you could. 

The concept "ArchitectTheNegativeSpace" extends the OpenClosedPrinciple to the limit. You have nothing - just empty slate ready to write on. Everything is opened for extension because there's nothing around it to be closed.

--PhlIp

''Can you explain more why this is not RefactorMercilessly ?  Your second attempt appears to be identical to that.'' --PeteHardie

T'is a goal of RM.

The parable illustrates what ATNS looks like when you got it. The parable must use a simulated design process as a narrative. Other illustrations are possible.

''I'm not seeing how this is dealing with the "negative space" - it reads more as a tale of the virtue of efficiency of materials, or even common sense - it's easier to build a better replacement hand than to add on an entire new arm'' --PeteHardie

''Maybe the principles on the CookDing page apply here?'' --MikeSmith

CookDing did not appear to apply here, to me --PeteHardie