We admit it, the Blog Wyrm staff enjoys one reoccurring reference and homage during April.  We love quoting, from the Waste Land by T.S. Eliot, the very famous line: “April is the cruelest of months”.  It is a pithy phrase that never fails to delight us due to both the artistry and the meaning and context that it can suggest.  Nonetheless, this April we are not inclined to reference it in any deeper way than we already have because we signs of hope in the waste land.  The signs are small and fragile, much like the first shoot of a germinating seed breaking the surface and seeking the light, but very real and encouraging.  This is hope that is born not out of ignorance of current affairs (worldwide inflation, COVID, the Ukrainian invasion, etc.) but in spite of these.  It is a hope predicated on the tenacity of the human spirit and the common sense shared by all people of good will.  It is with that slender shoot of hope, that wish everyone a happy Easter.

Now onto the columns.

As discussed in last month’s column, there are two quite different flavors of conditional probability; one arising from a joint probability distribution and one arising from the notion of transitions between states.  The problem posed in discussing the latter flavor was how to determine the probability of good weather in particular region given only the conditional probability that tomorrow will sunny or rainy given that today was sunny or rainy.  This month’s Aristotle2Digital shows how to solve this problem analytically and introduces the very powerful method of Markov Chain Monte Carlo.

Back in the nineteenth century, Frédéric Bastiat wrote extensively about economics, drawing particular attention to the concept of the unseen cost as a means of combating the many thoughtless and stupid approaches to economics popularly promulgated during his day.  One can’t help but wonder what he would have to say about our modern stupidity in which much the same thoughtless rhetoric is given a pseudo-intellectual imprimatur of pop psychology and served up surrounded by a shiny patina of social media.  We suppose he would just have to laugh.  And it is in the spirit of laughter that this month’s CommonCents compares the practical, no nonsense economics analysis of Larry Miler against the me-first approach of the modern mind in a little piece we entitle: When Larry Met Sally.

With much of the long hike up the conceptual mountain of classical thermodynamics behind us and the famous Clausius inequality in hand, this month’s UnderTheHood looks at the connections between entropy and the second law.  As part of this mountaintop vista, we can see 1) the well-known version of the second law, featured even in the Simpsons, between the forbidden nature of perpetual motion and the requirement that universal entropy always increasing, 2) what actually distinguishes spontaneous natural processes from those unnatural ones that require human intervention, and 3) a recasting of the first law that allows us to throw off the shackles of ‘inexact differentials’ and embrace a world of thermodynamic state variables.

Enjoy!