So many times changes are made to contracts that some folks argue is a cardinal change while others say no. When you do a FAR Search for "cardinal change" nothing is found. Is there a definition out there that will say clearly what the basic tenants are of a cardinal change. Is there a list of any kind out there?

There is not a single, clear definition. I suggest you read the discussion entitled "Meaning of 'Within the General Scope"' starting on page 382 of The Administration of Government Contracts, Fourth Edition.

I know we had some fun discussing efficient breaches in another thread. I believe that if the government directs a change that is found to be a cardinal change then that would constitute the government breaching the contract- inefficiently.

I always thought a cardinal change was one which was outside the scope of the contract as written and thus could not be redressed by a simple request for equitable adjustment to the contract price. A cardinal change is not covered by the Changes clause because it fundamentally alters the contractual requirements rather than change quantity, delivery point, etc.

I would use the example of a contractor being hired to pave 4 lanes of the the beltway between points A and B. if the contracting officer suddenly issued a change order directing the contractor to add two additional lanes as the contractor paved, that would be a cardinal change since is is outside the scope of the contract, namely paving.

Thus, an equitable adjustment is not appropriate as it is new work, and the contractor may not even be able to perform the work if he wanted, thus possibly setting up a default situtation due to no fault of the contrator.

Does it void the contract or is the directed change simply illegal. I would think the change would be illegal and unenforcable, and the contract as originally written would be considered unchanged.