Divine Logic


Divine Logic

27 September 2016
Edip Yuksel

114 Bismillah with 19 Letters

I would like to analyze the Quranic verses according to the rules of logic, especially symbolic logic. This project will have the following goals:

  1. To check the validity of the Quranic arguments
  2. To check the falsity of the opponent’s arguments quoted in the Quran
  3. To expose logical fallacies committed by commentators of the Quran
  4. To clarify the language of a verse
  5. To refute criticism directed to the Quran
  6. To clarify the nature and forms of the Quranic arguments
  7. To construct arguments from premises sharing common terms, dispersed among verses of the Quran, and drive conclusions that are not stated explicitly

To my knowledge, this will be the first of its kinds. I have expertise on both disciplines. I have translated the Quran into two languages. Quran: a Reformist Translation (Brainbow, 2007-2016) is a prime example of reading the Quran as a critical thinker rather than a dogmatic believer. In the endnotes of the translation, where my translation differs from Orthodoxy, I support it through linguistic analysis, Quranic context, rules of logic and philosophical arguments.

For this project, however, to evaluate the Quranic text, I will use the rules of Categorical Syllogism, Square of Opposition, and nineteen rules of inference detailed in the outstanding book, Introduction to Logic authored by Irving M. Copi, Carl Cohen, and Kenneth McMahon (Pearson, 1994-2016).

Let me provide a few examples:

Constructing arguments from premises sharing common terms, dispersed among verses of the Quran, and drive conclusions that are not stated explicitly.

Let me provide you with an example for the 4th kind from one of my articles on abortion I wrote in early 1990s, which I summarized at the footnote for verse 46:15 in Quran: a Reformist Translation (2007 Brainbowpress, USA)

“This verse informs us that the sum of pregnancy and breastfeeding is 30 months. When evaluated together with verse 31:14 suggesting the time of breastfeeding as 24 months, it takes simple arithmetic to learn that the pregnancy of the person (nafs) to be 6 months. It is common knowledge that pregnancy is longer than that. We know from modern embryology that the exact time for a normal pregnancy is 266 days (see 77:23). There is extra information to be extracted from these natural and scriptural signs. If we subtract the 6 months, that is 180 days, from 266 days, we get 86 days. We can easily infer that the Quran does not accept the creature inside the womb to be a person (nafs) from the time of conception until the 86th day of pregnancy. Other verses support our inference. For instance, verse 22:5 and 23:14, which explain the evolution of the human being in four stages, does not use the word person (nafs) or human (insan) to describe the early stages of pregnancy. The four stages of pregnancy are (1) sperm; (2) embryo; (3) about four-inch fetus (4) a new creature. It is clear that a new creation comes into existence after the 86th day. In other words, the emergence of consciousness/personhood (nafs) starts taking place in the brain of the fetus approximately three months after conception. Do we need to further add that reflecting on the ayat (signs) of the scripture together with the ayat (signs) of nature sheds light on the controversial issue of abortion? Also, see 16:58-59; 17:31”

Below is the summary of the argument:

  1. Quran condemns the action of child killing after birth (6:151; 17:31).
  2. Killing a person is a great sin (5:32).
  3. A person is more than a living being; person is consciousness (39:42).
  4. After a certain point in fetal stage a person emerges and a new person is created (22:5; 23:14).
  5. Embryo, the early stage of life in uterus, is not a “person” (46:15 and 2:233).
  6. The time for both pregnancy and breastfeeding is 30 months (46:15).
  7. The time for breastfeeding is 24 months (31:14).
  8. Human embryology is according to God’s law; nature is filled with divine signs (ayat) (30:20; 41:53; many more)
  9. We know from modern embryology that the exact time for a normal pregnancy is 266 days (see 77:23).

Therefore, abortion until the 86th day of pregnancy is not considered murder.

Expressing the premises and the conclusion above into standard symbolic logic forms may provide us with clearer insight regarding the validity of the argument. The argument, summarized above, can be further summarized as a combination of Hypothetical Syllogism and Modus Tollens:

  1. If fetus in early age does not have consciousness, then it is not a person
  2. If it is not a person, then aborting it is not murder

Therefore, if fetus in early age does not have consciousness, then aborting it is not murder

Writing it symbolically:

  1. p → q
  2. q → r
    .:p → r

And let’s continue the argument, by using the conclusion of the Hypothetical Syllogism above as the first premise of Modus Tollens:

  1. If fetus in early stage does not have consciousness, then then aborting fetus in early stage is not murder
  2. Fetus in early age does not have consciousness.

Therefore, Aborting fetus in early stage is not murder

We may symbolize the preceding argument:

  1. → r
  2. p
    .: r

Clarifying the nature of the Quranic arguments

The incomplete argument or the implied conclusion in verse 4:82 is interesting, since it could be considered in the form of two well-known logical syllogisms.

“Do they not reflect on the Quran? If it were from any other than God, they would have found many contradictions in it.” (4:82)

If the argument above is Modus Ponens, then it should read like this:

  1. If it were from any other than God, they would have found many contradictions in it.
  2. It was not from any other than God.

Therefore, they would not find many contradictions in it.

Symbolized as:

p →  q
.: q

(Here, I will not discuss whether “many” includes “any”)

If the same argument above is Modus Tollens, then it should read like this:

  1. If it were from any other than God, they would have found many contradictions in it.
  2. They have not found many contradictions in it.

Therefore, it was not from any other than God.

Symbolized as:

p → q
~ q
.: ~ p

Many commentators who are unaware of these two alternative inferences, end up making a philosophically weaker argument for Quran’s authenticity. Usually, they consider only the second argument, Modus Tollens, and leave the argument inconclusive, since the authenticity of the Quran remains open to any challenge regarding contradictions. In other words, the second argument is not dispositive; and always open to be discredited. As for the first argument, Modus Ponens, it is conclusive yet the antecedent of the first premise needs to be proven by another argument.

Clarifying the meaning of a verse

4:43  O you who acknowledge, do not come near the contact prayer while you are drunk, until you know what you are saying. Nor if you have had intercourse, unless traveling, until you bathe. If you are ill, or traveling, or one of you come from the bathroom, or you had sexual contact with the women, and could not find water: then you shall seek clean soil and wipe your faces and hands. God is Pardoning, Forgiving.

The language of the phrase regarding tayammum (ablution without water) appears to be difficult to understand; but expressing it in symbolic logic makes it much easier to understand:

“…If you are ill (p), or traveling (q), or one of you come from the bathroom (r), or you had sexual contact with the women (s), and could not find water (t): then you shall seek clean soil and wipe your faces and hands (u)”

{(pVq) V [(rVs) · t ]} → u

Thus, in case of illness or travelling, even if there is water, one still does not need to wash.

Exposing logical fallacies committed by commentators of the Quran

Formal and informal fallacies are frequently committed by Sunni or Shiite scholars in their understanding of Quranic verses. For example:

 “The believers are but brethren. …” (49:10)

Which is also translated as:

“The believers indeed are brothers. …” (49:10)

The verse above is read by many in a way to exclude non-believers; they stress “the believers” rather than “are brothers.”  Today many followers of Sunni and Shiite sects, especially Salafis, believe that the conjunction ‘but’ is used for exclusion, meaning that brotherhood is exclusive to the believers.[1]

This is a distortion through fallacy of accent. Accent occurs when the meaning of a text is changed by what word or words are stressed.

Since the Quran considers all humanity as Children of Adam, since it invites humanity to unite around One God, and it allows marriage with People of the Book, then the statement in 49:10 should be understood as an exclusive statement. It is like the parent of five children reminding the two older ones that they are but brothers and sisters. Thus, the stress should be on “are brothers.”

Refuting criticism directed to the Quran

6:151 Say, “Come let me recite to you what your Lord has forbidden for you: that you should not set up anything with Him; and be kind to your parents; and do not kill your born children for fear of poverty, We provide for you and for them; and do not come near lewdness, what is plain of it or subtle; and do not kill the person which God has forbidden, except in justice. That is what He enjoined you that you may comprehend.”

Critics claim that the language of the verse is unintentionally confused. They argue that according to its language, being “kind to your parents” is prohibited, which contradicts the intention of the author of the Quran, which is obvious in many other verses.

First, I should confess that our translation of the word “haram” does not exactly reflect its use in the Quran. It conveys prohibition or certain restriction regarding a behavior or act. For instance, four months are declared to be “haram.” It does not mean those months are bad. Or it does not mean that working, travelling, reading or numerous moral activities during those months are prohibited. It relates to a specific restriction or prohibition. It refers to the intertribal law prohibiting fighting and wars during those months, so that opposing parties could find opportunity to meet, discuss, resolve and negotiate a peace treaty.

Now let’s turn to the verse. If we accept the critics’ argument, then not only the instruction “be kind to your parents” all other instructions too must be contradictory to the other verses of the Quran. For instance, Quran does not prohibit not setting up anything with God. This would be a clear contradiction to the main message of the Quran: rational monotheism. So, some important prohibitions (not necessarily justifying a punishment by the society) are listed and the prohibition (haram) is not grammatically attached the succeeding list of 5 instructions.

  1. Do not set up idols
  2. Be kind to your parents
  3. Do not kill your children for fear of poverty
  4. Do not go near lewdness
  5. Do not kill a person, except to defend life against aggressor or killer

As you see, the meaning of none of the statements above is grammatically influenced by the word prohibition. However, all, with the exception of the second instruction, are negative. I admit that the affirmative statement “be kind…” violates the stylistic rule or structural harmony… However, it perfectly conveys the intended meaning: Be kind to your parents.

To clarify this point even further, I invite you to use “double negation” which is one of the “19 rules of inference”[1]

p ≡ ~ ~ p

Be kind to your parents ≡ do not be not kind to your parents

The double negated instruction in a better English: don’t mistreat your parents.

Logically, every affirmative instruction implies a negative restriction, and vice versa. So, now replace “be kind to your parents” with its logical equivalent form “don’t mistreat your parents” and you will see perfect fit to the list of restrictions.


[1] In Quran: a Reformist Translation, I did not translate “muminun” as “believers” since the word “believer” in English language depicts people who believe something without reason. The description of “iman” is different than “zann”, that is conjecture. Muminun are those who question their inherited religion and accept assertions based on reason and evidence. Thus, a more accurate translation of the word “muminun”, in the context of the Quran, is “acknowledging people” or “those who trust via evidence.”

[1] Introduction to Logic, Irving M. Copi and Carl Cohen, Prentice Hall, Eleventh Edition, 2001, page 361.