The general chemistry of acylammonium and pyridinium salts is reviewed along with the field of carbonyl-based nucleophilic catalysis. The knowledge from this overview is then used as a basis to compare both general base and nucleophilic catalysis. Due to their rate equations being mathematically equivalent (kinetically indistinguishable), a simplified method of interpretation is proposed which helps to evaluate which mechanism is operative. In particular, by use of this simplified, pre-equilibrium general base mechanism, many of the nucleophilic catalysis system exhibiting anomalous behavior (e.g. large solvent isotope effects) are clarified. Derivation of the rate expression for the pre-equilibration process show it to be indistinguishable from either general base or nucleophilic catalysis.