Models That Compute Are Superior

Howdy, Señor JoJo Morasco.  I start work in Yorktown Heights this week. 

Do you remember one of the epigraphs in my S. M. thesis, which was spoken by Drupada in the Mahābhārata: “Of beings, those that are endowed with life are superior.  Of living beings, those that are endowed with intelligence are superior.  Of intelligent creatures, men are superior.  Of men, the twice-born are superior.  Of the twice-born, students of the Veda are superior.  Of students of the Veda, those of cultured understanding are superior.  Of cultured men, practical persons are superior.”  As you indicated and this confirms, Indic thinkers of old held practical algorithms for computation in the highest regard, even higher than the ultimate for the Greeks: cultured understanding.

Here’s a quotation related to models and practicality that Pat Kreidl sometimes alluded to.  Box and Draper wrote in their book on empirical model-building, “Remember that all models are wrong; the practical question is how wrong do they have to be to not be useful.”

You asked how one learns scientific laws.  Schmidt and Lipson have a way that uses the power of evolutionary computation to find scientific laws via symbolic regression.  I don’t know if I’m fully down with this approach though, because symbolically stated laws and rules don’t allow for exceptions and uncertainty. 

One of the parts I thought was interesting in the second paper by Narasimha that you linked to was this: “Nīlakantha (1444-1545 CE), declared that ‘logical reasoning is of little substance, and often indecisive’ — words that would seem to go totally contrary to the approach that was used in Hellenist schools, which followed the Euclidean method of going from well stated axioms through a process of purely logical deduction to theorems or conclusions.”  Old school AI was all about logical deduction, and didn’t really deliver on its promise.  A new push that I think is poised to make an impact is the combination of logical stuff with statistical stuff — kind of in a way the combination of semantics with pragmatics — that this news article calls a grand unified theory of AI.  This combination/unification actually isn’t all too different from the “Newtonian synthesis” of axiomatism and computational positivism described in the Narasimha paper, innit?