Welcome ! The Logician is a rich lode of original writings on the theory and application of inductive as well as deductive LOGIC … and on Philosophy, Epistemology, Phenomenology, Modality, Causality, Psychology, Meditation, Ethics, Theology, Religions, and other interesting topics.


Avi Sion, Ph.D. (Philosophy)

Future Logic is an original and wide-ranging treatise of formal logic. It deals with deduction and induction, of categorical and conditional propositions, involving the natural, temporal, extensional, and logical modalities. This is the first work ever to strictly formalize the inductive processes of generalization and particularization, through the novel methods of factorial analysis, factor selection and formula revision. This is the first work ever to develop a formal logic of the natural, temporal and extensional types of conditioning (as distinct from logical conditioning), including their production from modal categorical premises. Preview selected results.

Phenomenology is the study of appearance as such. It is a branch of both Ontology and Epistemology, since appearing is being known. 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 particular appearance as a reality or an illusion is a complex process, involving inductive and deductive logical principles and activities. Opinion has to earn the status of strict knowledge.

Judaic logic: A Formal Analysis of Biblical, Talmudic and Rabbinic Logic is an original inquiry into the forms of thought determining Jewish law and belief, from the impartial perspective of a logician. Judaic Logic attempts to honestly estimate the extent to which the logic employed within Judaism fits into the general norms, and whether it has any contributions to make to them.

Buddhist Illogic : The 2nd Century CE Indian philosopher Nagarjuna founded the Madhyamika (Middle Way) school of Mahayana Buddhism, which strongly influenced Chinese, Korean and Japanese Buddhism, as well as Tibetan Buddhism. His writings include a series of arguments purporting to show the illogic of logic, the absurdity of reason. He considers this the way to verbalize and justify the Buddhist doctrine of “emptiness” (Shunyata). The present essay demonstrates the many sophistries involved in Nagarjuna’s arguments.

The Logic of Causation is a treatise of formal logic and of aetiology. It is an original and wide-ranging investigation of the definition of causation (deterministic causality) in all its forms, and of the deduction and induction of such forms. It deals with the main technicalities relating to reasoning about causation. Once all the deductive characteristics of causation in all its forms have been treated, and we have gained an understanding as to how it is induced, we are able to discuss more intelligently its epistemological and ontological status. Preview selected results.

Volition and Allied Causal Concepts is a work of aetiology and metapsychology. Aetiology is the branch of philosophy and logic devoted to the study of causality (the cause-effect relation) in all its forms; and metapsychology is the study of the basic concepts common to all psychological discourse, most of which are causal. This is a work of ambitious scope, intent on finally resolving philosophical and logical issues that have always impeded progress in psychology.

Ruminations is a collection of sundry notes and essays on Logic. These complement and enrich the author’s past writings, further analyzing or reviewing certain issues. Some important new insights are included here, such as the inductive understanding of negation.

Meditations : A meditation is a voluntary exercise intended to increase awareness, sustained over some time. The main purpose of the present Meditations is to inspire and assist readers to practice meditation of some sort, and in particular ‘sitting meditation’. This includes practices such as: observing the mechanisms of one’s thinking, stopping unnecessary thought, forgetting things about one’s self and one’s life that are irrelevant to the current effort of meditation, dealing with distractions, becoming aware of one’s breath, being here and now.

Logical and Spiritual Reflections is a collection of six shorter philosophical works. Hume’s Problems with Induction describes and refutes some of the main doubts and objections David Hume raised with regard to inductive reasoning. A Short Critique of Kant’s Unreason provides a brief critical analysis of some of the salient epistemological and ontological ideas and theses in Immanuel Kant’s famous Critique of Pure Reason. The four other works are: In Defense of Aristotle’s Laws of Thought; More Meditations; Zen Judaism; and No to Sodom.

A Fortiori Logic: Innovations, History and Assessments is a wide-ranging and in-depth study of a fortiori reasoning, comprising a great many new theoretical insights into such argument, a history of its use and discussion from antiquity to the present day, and critical analyses of the main attempts at its elucidation. Its purpose is nothing less than to lay the foundations for a new branch of logic, and greatly develop it; and thus to once and for all dispel the many fallacious ideas circulating regarding the nature of a fortiori reasoning.

Exposing Fake Logic is a collection of essays, written after publication of the book A Fortiori Logic, in which the author critically responds to derivative work by other authors who claim to know better. This is more than just polemics; but allows further clarifications of a fortiori logic and of general logic.

and OTHER WRITINGS – Avi Sion’s other writings include the above listed nine “Thematic Compilations” published at various dates, as well as some so far unpublished essays, which may be posted temporarily in a module called Topics.

Another derivative volume is Logical Philosophy: A Compendium (2013). This brings together five works by Avi Sion published in 2002-06, namely: Phenomenology (2003), Volition and Allied Causal Concepts (2004), Meditations (2006), Ruminations (2005), and Buddhist Illogic (2002). This collection does not include work done on The Logic of Causation in the same period (published in 2003, 2005).

Physical copies of all or some of these books have been donated to over a hundred and twenty university and public libraries across the world.

The above writings can be read online free of charge in ‘3D flipbook’ format at WWW.AVISIONBOOKS.COM. New!

All published books by Avi Sion can also be consulted free of charge in the Google Books and Google Play facilities. They are also available in WordPress.com and for subscribers to read in Scribd.com. Shorter works can be found in Tumblr.com. The abstracts and tables of contents of all the books can be consulted at Blogger.com.

Please read the Copyright Notice. The writings published in TheLogician.net have all been copyrighted by their author at different times, and are thus under the full protection of international and pan-American copyright conventions.

Many people, including me, find it easier to study from a paper book than reading on a computer screen; for the more technical topics, it would seem to me essential. You can purchase a printed copy of any of my books at CREATESPACE.COM and AMAZON.COM (in paperback), as well as at LULU.COM (in paperback, and also for the larger books, in hardcover) and other online stores (notably, BarnesandNoble.com). If you would like a printed book and cannot afford it, ask your local public or university library to order a copy.

You can also purchase all my books from Amazon.com and Lulu.com (follow links above) in ‘eBook’ form (kindle and epub, respectively). You can also buy and download all the books in Google Play, as well as in the online stores of: Apple’s iTunes®, iPhone®, iPad®, or iPod touch®, and Barnes & Noble’s Nook™. If you have a Sony or Kobo reader, you can also download some eBooks of mine from their stores.

Other external services: Check out AVI SION’S BLOG, which highlights various discoveries and ideas found in The Logician. You may post comments at the blog. The Logic Forum is a place where you can publish (free of charge) articles on logic, epistemology and related philosophical or scientific topics. The latter service also has a Guestbook and a Discussion Area to encourage feedback from you. (The Comments facility on The Logician website has been discontinued.) See also the book listings in the Open Library and in Online Books.

If you come across any technical glitch or typing error, or any factual mistake or error of reasoning, please do report it and it will be quickly corrected with thanks. Likewise, if you have any other comments or queries you would like me to respond to personally, feel free to write to the following e-mail address: avi-sion@thelogician.net – but preferably use the Readers’ Comments facility above described so other readers can partake and benefit. Please avoid personal questions and long dialogues.

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Study recommendations: These are large and complicated treatises, which attempt to answer certain ages-old philosophical questions in novel ways. They each took several years – thousands of hours – to develop and write, as their subject matters demanded; so do not expect to absorb them in a few minutes by reading a sentence here and a chapter there. They cannot be skimmed over casually, but require dedicated, attentive study over a long period of time. The most important chapters are not placed first or highlighted, but each subject is developed gradually and sequentially so that an intent student is sure to understand and profit.

Note that each book has an Abstract and a Table of Contents – look through these first, to get an overall picture. To gather momentum, read at least one chapter a week; but, to give yourself time to reflect, do not read more than one chapter a day. Always read the footnotes, they are intended as integral parts of the text. To navigate, use the buttons at the top (to choose a book) and on the left (to choose a part or chapter), and of course your browser’s back and forward arrows (to return to previously seen web pages). You can also use the General Sitemap.

Good reading! If you have the courage and you persevere, you will surely find it well worth the effort. “A journey of a thousand miles begins with the first step”…

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Launched: 11 May 2001.   Last edited: 10 January 2023.

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TheLogician.net was expanded and updated in 2023, thanks to the professional services of www.artechnity.com.