(Thanks to Skye for pointer)
RE: http://www.youtube.com/watch?v=n8m7lFQ3njk&feature=related
The attempt to better understand the physical structure of our brains doesn’t seem to have produced anything more useful than the philosophical insight that precise definitions, deduction in its three forms, and the syllogism as a means of comparing those definitions, and the use of analogies in their multitude of forms, are the minimum reducible objects of cognition and calculation by that process we call reason.
(Note: here are notes on deduction etc: Section III: Types of Analogical Argument)
The major improvement to human cognition have been: First the development of writing and accounting that allow us to communicate an idea consistently, and to perceive and compare what we cannot with our senses alone. And second, the use of statistics to create categories we could not perceive with our senses, and calculus to allow us compare multiple axis of causal properties, both of which draw upon our accumulated record of financial information — information that makes economic assessment, and therefore tests of our moral narratives, finally possible by other than purely philosophical means.
But in the end, empirical observation must be reduced to some categorical type which is in itself an analogy — and must be. Because we cannot perceive it by our senses alone.