There is another way of looking at bonding in benzene that preserves the language of single and double bonds. This is to say that an of the Keku16 and Dewar structures are partially correct, but that no one of them alone is a sufficiently good description of reality. The real benzene molecule in some way is a combination of all of them, like a mule is a combination of a horse and a donkey. Unfortunately, the term "resonance" has become associated with this viewpoint, and these partially correct structures are called resonance structures. This term gives the quite erroneous idea of a flipping back and forth among the several structures. The benzene molecule contains features of all five resonance structures, but it no more flips back and forth between them, than a mule "resonates" before your eyes from horse to donkey and back again. Nevertheless, the term resonance is so firmly embedded in the language of chemistry that we shall use it too. The 40 kcal mole of extra stability of the molecules over that of a KekuIe structure is called the resonance energy of the benzene molecules.