sentences:  It is important to clarify, however, that the induced fit concept cannot be used to rationalize catalysis.That is, the chemical catalysis is defined as the reduction of "E"a‡ (when the system is already in the ES‡) relative to "E"a‡ in the uncatalyzed reaction in water (without the enzyme).The induced fit only suggests that the barrier is lower in the closed form of the enzyme but does not tell us what the reason for the barrier reduction is.