Hi, how are you. My name is Paul Daniell. I study machine learning, logic, artificial intelligence, and economic theory. I am working on a book entitled The Foundations of Microeconomic Analysis, advised by Richard Bradley and J. McKenzie Alexander, both of the London School of Economics. The book defends the theory of deprojection, which I take to be a general epistemological phenomenon in scientific and everyday reasoning. Some years ago, I worked on a project, in some ways related, named The Limits of Interpersonal Probability, then advised by the late Patrick Suppes and, presently, Brian Skyrms of Stanford University. I teach logic, which I learned almost entirely from Tony Martin. This blog is foremost an opportunity for me to explain the theory of deprojection and its applications to microeconomic theory in a plainspoken way. If you have any comments or suggestions, you can reach me via email or Twitter (see below). If you so desire and time permits, you may deliver messages to me via carrier pigeon. Under no circumstances will a garden-variety rock dove be accepted as a substitute.

Paul Daniell. System B (Panasonic). September 2021.

Auf Deutsch

Mein Name ist Paul Daniell. Ich kann Deutsch. Aber mein Deutsch ist schlect. Willst du mit mir Deutsch schrieben? Maile mir. Viellecht wird es besser. Für mich ist Deutsch die schoenste Sprache auf der Welt. Es ist nicht meine Muttersprache. But—like—maybe ist es meine hübsche Tante. Das deutsche Wort für «pigeon» ist «Taube». I kann auch Französisch und Japanisch.

En Français

Je m’appelle Paul Daniell. J’ai appris le français au collège pour impressionner une fille. But—like—elle m’a d’abord aimé puis m’a détesté. Par conséquent, le français est compliqué pour moi. Le mot pour «pigeon» en français est «pigeon». Écrivez-moi si vous voulez écrire en français. Je peux écrire en japonais et en allemand aussi.


ポール・ダニエルです。私は日本語が大好きです。私にとって日本は東京です。 But—like— 東京は私にとって新宿です。私にメールを送ってください。鳩は英語で「pigeon」です。 私はフランス語とドイツ語も話します。`


வணக்கம் உள்ளே வா.என் பெயர் ஆங்கிலத்தில் எழுதப்பட்டுள்ளது. It is Paul Daniell. என் அம்மா பேசியது தமிழ்.

Paul Daniell. System X (Hasselblad). May 2022.


If your homing pigeon needs to send me something secretly, as did the war pigeons Cher Ami and William of Orange, then put this in their leg canister along with your message to paul.daniell@gmail.com.

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Paul Daniell. System B (Panasonic). December 2022.

Postal Address

If your homing pigeon really wants to deliver something by post, here is my address:

Paul Daniell
The London School of Economics
London WC2A 2AE
The United Kingdom

If your homing pigeon is in North America, here is a nicer address to land:

Paul Daniell
Department of Philosophy
c/o C.S.L.I.
Stanford University
Stanford CA 94305
The United States of America


When your homing pigeon flies back home, it deserves a break. Its fire-fangled feathers deserve to dangle on easy shores. Don’t let it make it just easy but splendid. It did a lot of good work. Here are such shores.

Harper Alerion My editor and chief editor of this blog. Stephen Handley Older brother. Alex Legolvan Younger brother. Henry Daniell Father. Richard Bradley My adviser, Doktorvater. J. McKenzie Alexander My adviser, Doktorbruder. Ed Zalta My boss and adviser. Uri Nodelman My boss and adviser.


I do not wish to receive unsolicited job offers. Your homing pigeon has missed its target, if it so arrives. If you are intent on hiring on someone like me, hire one of my students. To do so, contact Richard or the head of department here: LSE Philosophy.

Paul Daniell. System B (Panasonic). September 2021.


Your homing pigeon has better plain vision than me. It flies high and can see from lofty places. The closest thing I have to that is a camera. I shoot in System V (Hasselblad), System X (Hasselblad), System G (Nikon), and System B (Panasonic). For video, I shoot in System C (Canon). I shoot frequently on mobile phones such as System CD (iOS) and System CE (Android). I keep track of exposure and LUT information but don’t usually include it in the included caption. Email me if you want to know.

I learned photography by shooting first on a Mamiya C220. My favorite film is Velvia by Fuji at speed 400. I prefer to shoot 66 but can do 645 and. when necessary, 3:2. I prefer manual focus and can pull focus myself. If possible, on System B, C, and G, I use Sigma Art lenses.

Paul Daniell. System X (Hasselblad). May 2022.

Paul Daniell. System CD (iOS). November 2022.

A homing pigeon itself equipped with a camera is called a drone. I am licensed to operate those under 20kg in several countries and under 100kg in others. I call this System D. I program software for drones in C using Linux. I do not and will not use this software for any military purpose, so do not contact me if you wish to do so. In neooclassioal microeconomics, this is called a lexicographic preference, a mark of irrationality. So be it. Why so? That’s an easy one: however dark the picture, lenses are meant for light. Nevertheless, here are some dark pictures.

Los Angeles, U.S.A. System G (Nikon). Date unknown.

Tokyo, Japan. System G (Nikon). Date unknown.


A homing pigeon is so-called not because of its ability to target something. We homing pigeons are misunderstood. We fly fast. That is sometimes mistaken for anger. It is not. We deliver goods. Are we mere carriers? We are not merely anything. That’s what distinguishes a homing pigeon from a rock dove. We can be happy, we can be sad, we can be angry. Not merely. Here is a secret. We are called homing pigeons because we can find our way back home. We are selectively bred for precisely that reason. My name is Paul Daniell. I’m your homing pigeon. My home is London, England. We birds fly fast but only because we want to get home.

Paul Daniell. System CE (Android). December 2022.

Paul Daniell. System X (Hasselblad). May 2022.

Paul Daniell. System CD (iOS). May 2022.

Are homing pigeons weapons? No we are not. We are not eagles. We’re simple creatures. All we need is boundless love.


This blog is written in and produced entirely with free and open-source software, including but not limited to GNU/Linux, Python, ECMAScript, Java, LaTeX, Inkscape, and the GNU Image Manipulation Program. It is typeset in Computer Modern, designed by Donald Knuth and edited in Vi, originally authored by Bill Joy. On occasion, I post woodcuts and other royalty-free images to this blog, usually provided by Vault Editions.

Decidedly not a pigeon. Vault Editions. Date unspecified.