Karpathos, 2016


Me in my element. Rachel and I had a fab time traversing the island of Karpathos, Greece. On this particular adventure, once we descended to sea level, we found peace and solitude on an empty beach; a luxurious rarity only had when travelling on the cusp of the season.

Ancient Greek Coins Are Works Of Art

In the late 7th century BC the first coins were produced in the eastern mediterranean. By the early 5th century Greek minting city-states were commonplace. This rapid spread is a clear testament to the newly found usefulness of coinage (money) and that fact alone is enough to justify interest in their study.

But these coins were so much more than an economic convenience. These early coins were produced with a care and artistic craftsmanship on par with all the great artistic productions of the ancient Greek world – these coins are indeed pieces of art. And, in my opinion, the 5th and 4th century coins are the most beautiful coins ever produced.

To create these coins, the artists, called engravers, had to carve their subject matter into metal dies.  The dies were then used to strike a heated metal flan, thereby stamping the coin. Eventually the dies would break from repeated use and needed to be engraved again. This explains why so much variation is found in the finer details of these ancient coins, even when the overall subject matter of the coins remained consistent over time.

As an example, these authentic silver Athenian Owls were both minted contemporarily in Athens sometime during the last half of the 5th century BC. A detailed comparison reveals many subtle differences between the two versions (ignoring that somebody, presumably much later, scratched out the identifying letters alpha-theta-epsilon on the upper reverse). They are both beautiful and display an advanced level of craftsmanship and yet one Athena is slightly more beautiful than the other.

The Athenian Owl

It is generally agreed that the first minted coins came from Lydia in the late 7th century BC (Lydia is located now in western Turkey). Coinage spread quickly and by the 5th century most major Greek city-states were minting their own coins. Of the many beautiful coins minted in the ancient world, one coin stands above the others, and that is the Athenian Owl.

This Owl, a silver tetradrachm (four drachma) of standard weight (16.7 grams), was minted in Athens sometime in the latter half of the 5th century BC.  The obverse displays the patron of the city, Athena in her helmet. The reverse depicts an owl, a symbol of Athena’s knowledge and wisdom. As was typical, a tip of an olive branch and a half moon reside to the left of the head of the owl.  To the right are the letters alpha-theta-epsilon, “Athe”, an abbreviation for “of the Athenians’.

The owl was first minted in the 6th century BC and continued for centuries afterwards.  Due to the profound influence of Athens it was probably the first “internationally” recognized form of money.

Not surprisingly really, as soon as money was invented, in the form of minted coins that conformed to standard weights published by the minting cities, the debasement of currency was quick to follow. Thus, at some point on its ~2400 year journey to my collection this particular coin was tested for its silver purity as is evidenced by the deep cuts into its reverse side (it passed).

Perspective On A Cycle


This picture was taken at sunrise 7 days before the 2015 winter solstice which occurred on 12/22/15. We are looking southeast towards the Oakland hills from above Eureka Valley in San Francisco. The lone, tall redwood tree marks the approximate location of the terminus of the sun’s journey south on the horizon, after which, the sunrise will move northwards again until it reaches its summer terminus in six months to come. That point will occur quite a bit to the left of the frame of this photo!

Earthquakes, Know Them, Love Them

I published a new app named Epicenter on the Apple app store yesterday. Epicenter plots the latest 30 days of worldwide earthquake data supplied by the USGS on a beautiful globe.  The globe provides super responsive panning and zooming capabilities and is a treat in of itself!  While great on an iPhone, Epicenter is superb on an iPad!

You can find Epicenter here:  Epicenter – 30 Days Of Worldwide Earthquakes. If you like it, please give it a review!

Update: Epicenter now supports Today Widgets and the Apple Watch!

Economics & Complexity Theory


The study of economics and the physical sciences has been an interest of mine for some time.  Over the past two years I have been seeking specific examples of the application of nonlinear dynamics and complexity theory in economic research.  It turns out it’s a hot new field!

Reflecting on my readings it occurred to me that a mapping of the books I came across might be illuminating.  The result is this Book Map that graphically presents the linkages between subject matter, author and book (the book titles are hyperlinked to Amazon for easy access).

The journey led me to unexpected discussions in areas such as political science, sociology, anthropology, language theory, cognitive science, computer science and finance.  For example, Albin’s search for a scale from which to measure degrees of complexity in his dynamical models led him to Chomsky’s early work on defining the complexity of languages.  That was a pleasant surprise to me!

Many of the books in the map are technical .  I do own all of these books.  Some I have read multiple times and many have become reference books.

Use this link “Book Map” to obtain a copy of a PDF document that possesses working hyperlinks to Amazon.com.

A few of my very favorite titles are listed below:

  • Adam’s Fallacy – Duncan Foley
  • Barriers and Bounds to Rationality – Peter Albin
  • Currency Wars – James Rickards
  • Debt:  The first 5000 years – David Graeber
  • Nonlinear Dynamics and Chaos – Steven Strogratz
  • On Anarchism – Noam Chomsky
  • The Self Made Tapestry – Philip Ball

All of the books in this shortened list are approachable by anybody except Albin and Strogratz (Albin and Strogratz are very technical). Albin’s book contains an introduction by Duncan Foley that is the best overview description of complexity theory I have ever read (and I have read a few).  It’s a treat.  Strogratz is one of those rare teachers that can make the hard easy.