Acids hard and soft

Since polarizability means deformation of the electron cloud in an electric field, and since things that are easily deformed are soft, this led me to call the two classes of acids hard and soft, respectively. What I really had in mind was deformation in the presence of other atoms or groups, to which bonding was occuring. Thus optical polarizability, while a useful measure of softness, was not quite the correct measure. 

Take for example the reaction of two acids, hard and soft respectively, Aj and A, reacting with two bases, B, and B2, that are soft and hard respectively ... 

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