Category Archives: fourfolds

The Three Pillars of Stoicism

The Four Cardinal Virtues of Wisdom, Justice, Temperance, and Courage are often linked to the “Three Pillars” of Stoicism: Logics, Ethics, and Physics. Logics and rational thought enables the virtue of (practical) wisdom to produce intelligent assent or rejection. Ethics and moral strivings condition the virtue of justice (and courage) to inform proper action or non-action. Physics and natural constraints temper the virtue of courage (and temperance) by proportionate or bounded desire or aversion.

    • Logics (Rational Domain): Assent for (practical) Wisdom
    • Physics (Natural Domain): Desire for Courage and Temperance (restraint)
    • Ethics (Moral Domain): Action for Justice

Note the mismatch between Four Cardinal Virtues and the Three Pillars. Some add Metaphysics to get Four Pillars, although what domain does it inform? (Supernatural? Speculative? Philosophical?) Also note my use of the term “Logics”. If the British can use the term “Maths” then I can certainly use “Logics,” because logic can now come in many different formulations.

Further Reading:

The Highest Good: An Introduction To The 4 Stoic Virtues

Disciplines, Fields, and Virtues: The Full Stoic System in One Neat Package


The Spheres of Human Understanding

The Four Cardinal Virtues

Images of Logic, Ethics, Physics:



Linear Logic and the Laws of Excluded Middle and Noncontradiction

If LEM is the Law of Excluded Middle and LNC is the Law of Non-contradiction then

  • Classical Logic preserves both LEM and LNC
  • Intuitionistic Logic preserves LNC, but rejects LEM
  • Co-Intuitionistic Logic preserves LEM, but rejects LNC
  • Linear Logic broadly preserves neither, but narrowly preserves and rejects them with its pairs of conjunctive and disjunctive logical operators

Above is shown the four operators of Linear Logic and the statements for their preservation and rejection of LEM and LNC.

Further Reading:

Pete Wolfendale / Essay on Transcendental Realism
(at PhilPapers)





Four-Dimensional Vistas

The Fourth Dimension has been an interest of mine since I was a child. I’m not sure when I first heard about it, but I still have my coverless copy of “Geometry of 4 Dimensions” by Henry Parker Manning that I bought in a used book store. (I wonder why it hasn’t ever been reissued by Dover?) Maybe I heard about the fourth dimension in some science fiction TV movie, or in some mathematical survey book like “Mathematical Snapshots” or “Mathematics and the Imagination”.

Once I tried to explain to my best friend about my newly discovered insight how a hypercube could be folded up in four-dimensional space from its so-called three-dimensional net consisting of eight cubes, just as a regular three-dimensional cube could be folded up from its two-dimensional net of six squares. This 3D net somewhat resembling a cross is famously seen in Dali’s “Crucifixion (Corpus Hypercubus),” although I probably didn’t refer to this painting in my explanation.

I’m not sure who came up with the take-away message from my exposition, but it remains clear in my memory that the “junk in the middle” of the hypercube was a piece of the fourth dimension, just as the faces of a cube enclose a piece of our normal third dimension.

I recently came across Claude Fayette Bragdon, architect, author, draughtsman, stage designer, and mystic. At first I was interested in his drawings found on-line. His book “Four-Dimensional Vistas” started off with a good if overly wordy introduction to the concept of the fourth dimension. But then he suggests that many esoteric concepts such as the meaning of dreams, reincarnation, past-life regression, prognostication, ESP, etc. could possibly be explained by higher dimensional space or even higher dimensional time.

Even though I initially found many of these hypotheses too far-fetched for my tastes, I still found some interesting ideas to mull over in this little book.

Further Reading:

The art of Claude Fayette Bragdon, 1866–1946

Claude Fayette Bragdon / Four-Dimensional Vistas (1930)

Claude Fayette Bragdon / The Beautiful Necessity (1910)

Claude Fayette Bragdon / Architecture and Democracy (1918)

For my gratuitous anime tie-in, Bragdon’s world-view suddenly reminds me of the anime character  Haruhi Suzumiya, who wished for her aliens, time-travelers, and ESPers so much that she willed them into being. If only she had known about the fourth dimension!

[*3.139, *12.121, *13.50]



The Circumplex Model of Affect

James Russell developed a circumplex model of emotion, not to be confused with the interpersonal circumplex. (There are a variety of circumplex models for various subjects, since they are merely circular and continuously scaled in nature.)

This model is also called Emotional Valence and Arousal, where Valence ranges from Negative to Positive (or Unpleasant to Pleasant) and Arousal ranges from Low to High (or Mild to Intense). We get the fourfold partitions of

  • Mildly Unpleasant
  • Mildly Pleasant
  • Intensely Unpleasant
  • Intensely Pleasant


  • Low & Negative
  • Low & Positive
  • High & Negative
  • High & Positive

There are several way to discretize this circumplex into eight parts, but here is one from Russell (1980).

  • Aroused
  • Excited
  • Pleased
  • Contented
  • Sleepy
  • Depressed
  • Miserable
  • Distressed

Compare with the concept of Flow, where the variables are challenge and skill, instead of arousal and valence.

Further Reading:

James Russell / A Circumplex Model of Affect, J. of Personality and Social Psychology 1980, Vol. 39, No. 6, 1161-1178

James A. Russell, Maria Lewicka, Toomas Niit / A Cross-Cultural Study of a Circumplex Model of Affect, J. of Personality and Social Psych. 1989, Vol. 57 No. 5, 848-856

Jonathan Posner, James A. Russell, Bradley S. Peterson / The circumplex model of affect: An integrative approach to affective neuroscience, cognitive development, and psychopathology
Dev. Psychopathol. 2005, 17(3), 715-734


Eugen Rosenstock-Huessy and His Cross of Reality

Imperative (prejective), conjunctive or optative (subjective), preterite or perfect (trajective), neutral indicative (objective) are grammatical necessities arising out of times and spaces.

— Eugen Rosenstock-Huessy

Further Reading:

Click for PDF:  Martin Zwick / Rosenstock-Huessy’s “Cross of Reality” and Systems Theory

Martin Zwick / Ideas and Graphs: the Tetrad of Activity

Click to access QUADRILATERAL%20TEACHING.pdf

Caryl Johnston / Grammar, Speech, Rhetoric, & the Fate of Humanity

[*13.44, *13.46]




The Passions of the Stoics

I will show you fear in a handful of dust.

— From “The Waste Land”, by T. S. Eliot

The Stoics divided the passions into four parts, consisting of a two by two matrix of “good” or “bad” emotions versus whether they occur during the present or while thinking about the future.

  • Delight (or Pleasure): present and good
  • Distress: present and bad
  • Desire (or Appetite) : future and good
  • Dread (or Fear): future and bad

To Stoics all these passions were actually harmful, in the sense that they are irrational and instead should be thoughtfully managed. Instead one should have Three Good Feelings and but not Three Not-as-Good Feelings:

  • Joy (chara) instead of Pleasure
  • Wish (or Hope) (boulesis) instead of Appetite
  • Care (eulabeia) instead of Fear

What about Distress and its Stoic version (which might even be Calm or Ease)? And what of emotions for past memories? They might be  Relief (past and “bad”) and  Regret (past and “good”).

Further Reading:

Stoic Ethics




The Four Immeasurables

May all beings have happiness and the causes of happiness.
May they be free of suffering and the causes of suffering.
May they never be separated from supreme joy beyond all sorrow.
May they abide in equanimity free from attachment and aversion.

— Buddhist Prayer

I’m currently watching a beautiful anime called “The Heike Story”, based on the Japanese Tale of the Heike. The central character is a child plagued with the ability to see visions (usually of death and destruction) of the future and remote events. She is anguished to witness  these and is powerless to do anything about them,  but finally (spoilers!) determines that she might ease her mind by praying for those involved.

This character is not portrayed as any sort of  religious individual, so I wondered what kind of prayer might be appropriate for her. Searching for an “Atheist Prayer”, I quickly found the Buddhist Prayer above that might be something like she would say, that encodes the “Four Immeasurables” of Buddhist thought. This prayer is not offered to any god or gods, but just a wish and hope for those in mind and indeed for all sentient beings.

The Four Immeasurables of Buddhism are

  • Maitri: Loving kindness
  • Karuna: Compassion
  • Mudita: Sympathetic Joy
  • Upeksha: Equanimity

Further Reading:

The Four Immeasurables


The Four Elements of Thinking

While searching for something else I chanced upon “The Four Elements of Thinking: Reasoning, Creativity, Synthesis, Evaluation” by Benjamin Cheung, Ph.D., published in 2019. Any book about the four classical elements being used as metaphors for other things is of personal interest, plus that the things being four aspects of thinking was immediately intriguing. Dr. Cheung divides thinking into the four aspects of the subtitle, plus he divides each aspect into four sub-aspects or skills as follows:

    • Reasoning (Earth Thinking)
      • Evidence
      • Inductive Reasoning
      • Deductive Reasoning
      • Abductive Reasoning
    • Creativity (Air Thinking)
      • Investigation
      • Incubation
      • Insight
      • Innovation
    • Synthesis (Water Thinking)
      • Linking
      • Perspective
      • Synthesis
      • Pivots
    • Evaluation (Fire Thinking)
      • Decisions
      • Judgments
      • Contingency Plans
      • Validation

Note his choice in assignment of the Classical Four Elements to each of these aspects of thinking. I would have assigned them differently: Reasoning to Fire, Creativity to Earth, Synthesis to Air, and Evaluation to Water. The price of the e-book is reasonable, so I may investigate the “thinking” behind his alignments by purchasing and reading further.

He also has an interesting book on collections of ideas which he arranges into a “periodic table,” which might be analogous to a more modern scientific elemental assignment. Additionally, he has had Kickstarters on playing or flash cards for both books, which is a notion somewhat dear to my heart (See A Game of Fourfolds).

I have mentioned thinking or thought often in this blog, and believe that poor thinking or irrational thinking is greatly to blame for many of our current ills. Blame can also be attributed to poor communication skills. The best thinking can be obscured by poor communication. What is the best theory of the linkage between thought and language?

Further Reading:

Benjamin Cheung, Ph. D. / The Four Elements of Thinking: Reasoning, Creativity, Synthesis, Evaluation

Link to Amazon



Maxwell Relations

Maxwell Relations are commonly known as a set of four partial differential equations between four thermodynamic quantities or potentials: pressure (P), volume (V), temperature (T), and entropy (S). So for example the expression (∂T/∂V) |S  means the partial derivative of T with respect to V while keeping S constant.

    • (∂T/∂V) |S = -(∂P/∂S) |V
    • (∂P/∂T) |V = (∂S/∂V) |T
    • -(∂S/∂P) |T = (∂V/∂T) |P
    • (∂V/∂S) |P = (∂T/∂P) |S

In my diagram above, the expressions that are equal are on either side of the common leg of adjacent isosceles right triangles.

Further Reading:

Thermodynamics and the Four Thermodynamic Potentials

[*12.194, *12.195]


Linear Process Algebra

One of computer scientist and Professor Emeritus Vaughan Pratt’s most recent conference papers is on “linear process algebra,” which relates several of his previous interests on linear logic, Chu spaces, concurrent processes, events and states, etc.

The paper opens with a nice overview of computer science research primarily concerned with concurrent processes. Computation itself divides into the aspects of logical and algorithmic, formal methods into the logical and algebraic, concurrent computation into operational and denotational, and then the author gives a brief list of models of processes by a variety of mathematical structures until he comes to his theme of using Chu spaces.

As an example, he presents processes as Chu spaces over the set K, where K = { 0, T, 1, X}, with names and meanings :

  • 0: Ready
  • T: Transition
  • 1: Done
  • X: Cancelled

and then details four binary operations as working in Chu spaces over K:

  • P ; Q: Sequence
  • P + Q: Choice
  • P || Q: Concurrence
  • P ⊗ Q: Orthocurrence

Further Reading:

Vaughan Pratt / Linear Process Algebra

Click to access bhub.pdf

Click to access lpa.pdf

Click to access bud.pdf