Practical Reason, Progressive Reason, Experimental Reason

In the Second Thesis of Idea for a Universal History, following his introduction of what, as has been previously discussed, can be termed 'Progressive Reason', Kant further characterizes this faculty as requiring "trial, practice, and instruction in order to gradually progress".  Thus, the appreciation for Experimental Reason that he expresses in the Preface to the B edition of the 1st Critique is more than extrinsic whimsy.  Indeed, if, as has been previously proposed here, Pure Practical Reason is Progressive Reason, i. e. is an animator of innovative conduct, and Progressive Reason proceeds by trial and error, then Pure Practical Reason is also Experimental Reason.  This interpretation of Kant's concept is not easy to glean from a focus on his Deontological and Theological writings that ignores the Idea for a Universal History.