Schopenhauer’s Four Laws of Thought

The first three of Arthur Schopenhauer’s Four Laws of Thought are pretty much the same as the classical three laws of thought. Schopenhauer added a fourth law that was basically for his Principle of Sufficient Reason.

  • Identity
  • Non-contradiction
  • Excluded middle
  • Sufficient reason

These Four Laws are often given in two flavors: the first, in fairly concrete terms of subjects and predicates, and the second, more glib in terms of existence and being and such (isness).

  • A subject is equal to the sum of its predicates. Everything that is, exists. (Identity)
  • No predicate can be simultaneously attributed and denied to a subject. Nothing can simultaneously be and not be. (Non-contradiction)
  • Of every two contradictorily opposite predicates one must belong to every subject. Each and every thing either is or is not. (Excluded middle)
  • Truth is the reference of a judgment to something outside it as its sufficient reason or ground. Of everything that is, it can be found why it is. (Sufficient reason)

The phrase ‘it can be found’ sounds like a constructive method rather than a mere existence proof, but the common theological technique that combines both by saying “everything happens for a reason” avers the reason to an ineffable deity. (I bet Schopenhauer would have disliked this view because from what I understand he was an atheist.)

Moving on, I would like to represent these four laws in even more concrete terms of logical expressions. In the following attempt, let a, b be subjects (or objects), and P, Q be predicates (or qualities):

  • ∀a (a ≡ ∀P P(a))
  • ∀a ¬∃P (P(a) ∧ ¬P(a))
  • ∀a ∀P (P(a) ∨ ¬P(a))
  • ∀a ∃b (b → a)

When detailed in this way, these four laws don’t seem very complete, or don’t quite form a unity, as implication and equivalence are each in only one of them. Even though it doesn’t help that criticism, perhaps one can succinctly say:

  • Things can be reduced to (all) their qualities.
  • Qualities are disjoint from their opposites.
  • Qualities and their opposites are sufficient.
  • Things are entailed by some thing (possibly same).

In addition, I quite liked this Goodread review which aligns Aristotle’s Four Causes with Schopenhauer’s Fourfold Root. So then:

  • From Parts : Material Cause : Becoming : Identity
  • For Functions : Final Cause : Knowing : Non-contradiction
  • Into Structures : Formal Cause : Being : Excluded-middle
  • By Actions : Efficient Cause : Acting : Sufficient reason

Further Reading:

[*11.196, *11.197]


At some point, I need to understand the difference between the law of the excluded middle and the principle of bivalence.


Carl Jung’s Alchemical Tetrameria

Jung’s diagram of his alchemical tetrameria is supposed to represent the evolving self, and suggests movement, succession, and change and yet stillness, consistency, and renewal. His own diagram is quite different from mine, but I do think that mine has some merit.

What are those elements A, B, C, D, and a, b, c, d, and the subscripts 1, 2, 3, 4, indicating the modification of them? I’m not quite sure that it matters, except that for the relationships between the two, and the relationships between the four squares, and the relationships between the four parts of the four squares.

In Jung’s diagram, A equals a cycle of a, b, c, and d, and likewise B a cycle of a1, b1, c1, and d1, etc., and so we can instead say A is a cycle of Aa, Ab, Ac, and Ad, and likewise B is a cycle of Ba, Bb, Bc, and Bd, etc. In that sense my diagram denotes much the same as Jung’s.

Nevertheless, I’m going to have to cycle through some more thoughts about why one should spend too much time contemplating this diagram.

Further Reading:

Murray Stein / Jung’s Map of the Soul: an introduction

Leslie Stein / Becoming Whole: Jung’s equation for realizing God

Carl Jung / Aion

[*12.10, *12.11]


The Growth-Share Matrix

This blog obviously needs more cute animals, right? So to symbolize the Growth-Share matrix of product marketing I give you the diagram above.

  • Dogs or Pets: low market share, slow growing industry
  • Cash Cows: high market share, slow growing industry
  • Stars: high market share, fast growing industry
  • Question Marks: low market share, fast growing industry

Please refer to the article below for more explanation.

Further Reading:




The Prospect Theory of Kahneman and Tversky

Like it or not, we are all betting individuals. But what interactions are there between the perceived and actual probabilities of things happening and the choices made for or against them? The likelihood of their occurrence, coupled with the size of the gains or losses from anticipating and acting on them, show that people are not entirely the rational agents that we think they are.

Instead of armchair introspection, careful experimental methods were used to give us these (not so) unexpected results. What is demonstrated is that deciding individuals make asymmetric choices based on their poor understanding of relative likelihoods. All sorts of biases and poor thinking on our part contribute to non-rational evaluations of how we end up choosing between alternatives.

The findings are that the near certainty of events happening is undervalued in our estimation, and the merely possible is overvalued. So those things very likely to occur have a diminished weight in our minds, and those things unlikely but possible have an increased weight. These are called the certainty effect and the possibility effect, respectively.

  • Likely Gain (Fear)
  • Likely Loss (Hope)
  • Maybe Gain (Hope)
  • Maybe Loss (Fear)

This asymmetry in valuation leads fearful individuals to accept early settlements and buy too much insurance, or hopeful individuals to buy lottery tickets and play the casino more often then they should if choosing optimally. What factors contribute to this behavior? Emotions, beliefs, and biases, probably all play a role in these perceived payoffs between dread and excitement.

In some “Dirty Harry” movie, the lead character essentially asks “do you feel lucky, punk?”, to goad another into taking a risk. In the movie “War Games”, the supercomputer more or less temptingly asks, “would you like to play a game?”, to encourage the playing of unwinnable matches. Watch out for those that know how to play the odds of hope and fear to manipulate our prospects and decisions.

Further Reading:

View at

Daniel Kahneman / Thinking Fast and Slow