The logo you see at the top of the Phronesis blog is rendered in Fragment Core, a wonderful font from sugargliderz.
It's free, which is always a good start, and fits the Phronesis concept perfectly.
NB You may want to read this post with one eye on the Fonts.com 'anatomy of a character' glossary.
The logic behind Fragment Core
With its clear character spacing and circular bowls, Fragment Core is ideal for display text - making it perfect for this header image.
However, its typewriter style also permits its use in longer sequences, such as the three principles of phronesis that occupy the right-hand side of the logo.
It is, in places, without serifs - notably the terminals of the 'e' and the top of the 's' - while elsewhere its adornments are subtle, adding elegance without detracting from legibility.
Importantly, Fragment Core is relatively wide, allowing a banner image to be created which does not push the main content of the site off of the screen - even with those three lines of text at its right.
There is also a lovely bespoke quality to the typeface, giving the sense of typewriter output that has been hand-traced and perfectly encapsulating the sense of 'ordered creativity' for which the Phronesis concept calls.
Other Phronesis typefaces
If the Phronesis blog is displaying as intended, the main text of the page will be in Corbel, a sans-serif typeface whose line height and general character shape is fairly complementary to Fragment Core, but better designed for block paragraphs.
Even if you do not have Corbel installed, you should instead see a similar sans-serif typeface with circular bowls - Verdana or Arial, depending on which you have available on your computer or mobile device.
Much as the colour scheme is a deliberately minimal selection of complementary purples, the typefaces used here were carefully selected and, I hope, help to convey the concept of Phronesis to those unfamiliar with the term itself.