header photo

The Laws of Thought

A Thematic Compilation by Avi Sion

Blog posts November 2017



Table of Contents


1.         Chapter One

1.         The Law of Identity

2.         The Law of Contradiction

3.         The Law of the Excluded Middle


2.         Chapter Two

1.         True or False

2.         Bran…

Read more

1. The Foundations of Logic


Logic is founded on certain ‘laws of thought’, which were first formulated by Aristotle, an ancient Greek philosopher. We shall describe them separately here, and later consider their collective significance.


1.     The Law of Identity


The Law of Identity is an impe…

Read more

2. Logical Relations


1.     True or False


Reality and illusion are attributes of phenomena. When we turn our attention to the implicit ‘consciousness’ of these phenomena, we correspondingly regard the consciousness as realistic or unrealistic. The consciousness, as a sort of peculiar relation betwee…

Read more

3. Credibility


1.     Ground of the Laws


We began our study by presenting the laws of thought — the Laws of Identity, of Contradiction, and of the Excluded Middle — as the foundations of logic. We can see, as we proceed, that these first principles are repeatedly appealed to in reasoning and v…

Read more

4. Paradoxes


A very important field of logic is that dealing with paradox, for it provides us with a powerful tool for establishing some of the most fundamental certainties of this science. It allows us to claim for epistemology and ontology the status of true sciences, instead of mere speculative digres…

Read more

5. Double Paradoxes


1.     Definition


We have seen that logical propositions of the form ‘if P, then nonP’ (which equals to ‘nonP’) or ‘if nonP, then P’ (which equals to ‘P’), are perfectly legal. They signify that the antecedent is self-contradictory and logically impossible, and that the conseque…

Read more

6. The Tetralemma


1.     The Tetralemma


Western philosophical and scientific thought is based on Aristotelian logic, whose founding principles are the three “Laws of Thought”. These can be briefly stated as “A is A” (Identity), “Nothing is both A and non-A” (Non-contradiction) and “Nothing is nei…

Read more

7. A New Phenomenology


1.     Phenomenology


Phenomenology may be defined as the study of appearances as such. By an ‘appearance’ is meant any existent which impinges on consciousness, anything cognized, irrespective of any judgment as to whether it be ‘real’ or ‘illusory.’ The evaluation of a particul…

Read more

8. Existence, Appearance, Reality and Illusion


1.     Appearance and Other Large Concepts


By ‘appearance’ is meant, first of all, anything and everything – but upon reflection, more specifically anything which ‘comes to mind,’ by whatever means. This is not a definition, but an indication. The term appearance is too fundam…

Read more

9. Compatibility or Incompatibility


1.     Apprehension


Allied to sameness and difference are the concepts of compatibility or incompatibility, which underlie what Aristotle has called the three ‘laws of thought’ – identity, non-contradiction and exclusion-of-the-middle. How do we apprehend things (percepts, intui…

Read more

10. Thinking Logically


1.     Logical Attitudes


Logic is usually presented for study as a static description and prescription of forms of proposition and arguments, so that we forget that it is essentially an activity, a psychic act. Even the three Laws of Thought have to be looked at in this perspect…

Read more

11. Understanding Axioms


1.     Dialectical Reasoning


The three “Laws of Thought” may be briefly explicated as follows:


  1. Thesis: there are certain appearances; appearances appear.
  2. Antithesis: there are incompatibilities between certain of these appearances; in such cases, one or both of…

Read more

12. On Contradiction


1.     Contradiction


Many people misunderstand what we logicians mean by ‘contradiction’. The contradictory of a term ‘A’ is its negation, ‘not A’, which refers to anything and everything in the universe other than A, i.e. wherever precisely A is absent in the world. The relat…

Read more

13. Active Reason


1.     Special Status of the Laws


The three Laws of Thought must not be construed as some prejudice of Aristotle’s, which some scientific discovery – like the particle-wave duality or the relativity of space-time measurements – could conceivably raise doubt about or displace. Th…

Read more

14. The Phenomenological Approach


1.     Appearance, Reality and Illusion


Phenomenology results from a realization that the building blocks of knowledge are appearances. This realization is obtained through a dialectic, comprising thesis, antithesis and synthesis, as follows.

  1. At first, one naturally regard…

Read more

15. Fake Logics


1.     Poles of Duality


Concerning the principle, advocated by many, especially oriental, philosophers, that poles of duality (e.g. good-bad, light-dark, etc.) arise together – certain comments are worth making.

Oriental philosophers pursue a non-sorting mode of consciousne…

Read more

16. On Negation


1.     Negation in Adduction

Concepts and theories are hypothetical constructs. They cannot (for the most part) be proven (definitely, once and for all), but only repeatedly confirmed by experience. This is the positive side of adduction, presenting evidence in support of rational con…

Read more

17. More on Negation


1.     Formal Consequences


Returning to logic – our insight [earlier] into the nature of negation can be construed to have formal consequences. The negative term is now seen to be a radically different kind of term, even though in common discourse it is made to behave like any…

Read more

18. The Principle of Induction


1.     The Uniformity Principle


Concerning the uniformity principle, which Hume denies, it is admittedly an idea difficult to uphold, in the sense that we cannot readily define uniformity or make a generality of it. We might speak of repetition, of two or more particular things …

Read more

19. The Primacy of the Laws


1.     Briefly Put


Aristotle’s laws of thought cannot be understood with a few clichés, but require much study to be fathomed. The laws of thought can be briefly expressed as[1]:

  1. A thing is what it is (the law of identity).
  2. A thing cannot at once be and not-be (the la…

Read more

20 blog posts

Blog Search

Blog Archive


There are currently no blog comments.