A Compilation of Islamic Philosophy and Theology [edited]

Chapter Two: Research Methodology in Philosophy

The aim of this chapter is to define research methodology in philosophy. For this purpose, we should first of all understand what is meant by ‘’ research methodology’’ in any particular field of study. Since research methodology in a field of knowledge is nothing other than the method of determine the truth or falsity of its constituent propositions and because the truth or falsity of the propositions of a real universal field of knowledge can only be determined by either a rational or an empirical method, we must begin by explaining this last point, according to which propositions are divided into a priori and a posterior.

Next, we shall divide different types of knowledge into rational and empirical and finally try to prove that philosophy is a form of rational knowledge.

A Priori and Posterior Propositions

Consider the geometrical proposition ‘’ the sum of the internal angles of a triangle is 180 degrees’’ and the physical proposition ‘’ all metals are expanded by heat.’’ Both of which are correct and compare them with each other. It is clear that if in the course of experience we came across a triangle whose qualities are different from those stated in former proposition, we would not judge that proposition to be false and invalid; however, if we found a kind of metal which did not have the quality mentioned in the physical proposition we would consider that proposition false and they deny its universality. What is the reason for this difference? The reason lies in the methods used to prove the truth or validity of these two propositions. The truth of the first proposition is proved by a rational method while that of the second is proved by an empirical one. By a rational method we mean a form of demonstration that ultimately rests on primary, self-evident propositions. Since understanding the truth of primary, self -evident propositions and the law of reference in logic ,on which this types of demonstration is based , are both independent from experience and the intellect understanding the truth prior to experience and independent of experience and does not need its help.

The truth of the second proposition, however can only be understood following experience and though its assistance. The some can also be said of false propositions in that the fallacy of some of them can be understood independent of experience while only the help of experience can ascertain that of others. In technical terms, proposition of the second kind are called a posterior.

Therefore a prior proposition is one whose truth or falsity can only be determined by an empirical method. It is important at this junction to consider the following point.

The first Point

The concepts employed in a proposition may have been acquired through the sense but it may still be a priori if we can determine its truth or falsity by a rational method and independent of the senses, like many geometrical propositions.

Which though contain many sensible concepts, such as dot?Line surface, circle, triangle etc. are all a priori since we can determine their truth or falsity by the rational method and without the help of the sense. In general the way parts of a proposition or the whole proposition have entered the mind, whether it is through dreams, inspiration etc. Does not make a proposition a priori or a posterior. Whether a proposition a is a posterior depends only on the way we determine its truth or falsity.

The Second Point

Aposterior proposition is exceptive; that is, observed counter - example can only question it universality while retains its validity or other cases. In other words, though that proposition is false in its universality, in its more particular form it may be true. Consequently, another universal proposition but with a particular subject replaces the invalidated universal proposition. A prior proposition, however is non-exceptive, that is a rational counter example will indicate the total invalidity of the proposition and we cannot claim its truth in any other case. For example suppose a true geometrical proof demonstrates that the total sum of the angles of an equilateral triangle is not 180 degree.

This counter example will show that triangle is 180 degree is not valid and the invalidity of that cannot rationally judge that the total sum of the angle of any triangle is 180 degree.

Rational and Empirical Forms of Knowledge

Rational knowledge is that knowledge whose proposition are a priori while empirical knowledge is that knowledge whose proposition are a posterior In other words rational knowledge is the form of knowledge whose proposition can be proved true or false by a rational method while empirical knowledge is one whose propositions can be proved true or false only by an empirical method.

Keeping in mind that by ‘’research methodology’’ in one kind of knowledge we mean that method which determine the truth or falsity of its proposition we can say. Rational knowledge is the kind knowledge is one whose research methodology is empirical. From now on we shall use the word ‘’ knowledge ‘’ to refer to all forms of knowledge and science and the word ‘’science ‘’ in accordance with the current usage of the term to indicate empirical knowledge alone.

Philosophy is Rational Knowledge

Initially, using the reduction ad absurdum argument, we shall prove the validity of this claim in respect to a single philosophical proposition, such as the principle of causality as an example. Then in 3.2 we will prove its validity concerning all philosophical propositions.

Example: The law of Causality is not empirical

Let consider the principle of causality in it conventional sense: Every phenomenon, namely everything crated in time (temporal) needs a cause. Suppose this is and a posterior proposition and its truth or falsity can be demonstrated by experience. We will try to show that, firstly this cannot be done without employing a prior proposition and secondly, it will lead to a vicious circle.

According to the practice followed by philosopher of science in falsifiability or verifiability of empirical proposition , the above proposition can be a posterior if is truth can be demonstrated by experience (according to the principle of verifiability in the empirical science ) or its falsity could be justified experimentally (according to the principle of falsifiability in empirical science ). In other words either its truth should be proved by experience and inductive generalization or certain empirical states or inductive imagined. Which if realized would demonstrate the inaccuracy of that proposition. To be more precise either we have to show phenomena and secondly need a cause and then generalize this finding to include all phenomenon needs a cause or we must imagine certain states and conditions in which we could prove by experience that is certain thing is first of all a phenomenon and secondly does not need a cause is falsifiable and a posterior, therefore in both approaches we must initially show by experience that certain thing or things are phenomena. However, we can easily prove that, firstly, this cannot be done through experience alone and without employing a prior proposition and secondly, that it entails a vicious circle.

To explain, we should say that being a phenomenon means being created in time. This in turn means that the thing in question must be initially non-existent and then later on become existent while we con not perceive the existence to nonexistence of things through the sense (aided or unaided ) This is so since perception require two preconditions: firstly, the object in question must leave a trace of its effect on the perceiving organ - of course this effects is going to be corporeal and must pass though different stages until it reaches the brain - and secondly the spirit must perceive this effects. Therefore only such things can be sensible that effect the cells of one of the sense organ In the light of this if we look closely into our perceived we will see that the only things that can be perceived directly by the sense are colour different kinds of noises, taste, smells, cold and heat, smoothness and roughness, hardness and softness, dryness and wetness .Lightness and heaviness, Moreover there are other things which are also perceived through the sense, but not the same manner as the qualities just referred to, for these do not directly affect the sense organ rather assisted by a form of intellectual analogy, are perceived along with those things which directly affect the sense organs,Wecall this kind of perceived ‘’ indirect sense perception.’

Now the things that are perceived indirectly by the sense are different kind of shaped. number, the position which things have in relation to each other, in terms of being remote ,close ,joined or separated from each other being above below to the left or to the right of each other and so on. Some philosophers also hold that temporal succession of thing and their movement can only be perceived indirectly by the sense.

Therefore certain attributes such as necessity, possibility, impossibility, causality or influence, being an effect or affectability, condition,conditioned, potentially, actuality, dependence, independenc , self- sufficiency, contrary , contradiction, temporality or being a phenomenon, pre-eternity, substantiality, accidentally, different kind of substance existence and non - existence can neither directly nor way left to perceive the temporality of a thing and that is form the fact that we do not perceive it at first and then come to perceive it. For example, we do not initially perceive a light and then at a certain moment we begin to see it. From this we conclude that it was non-existent at the beginning and then it became existent; in other words, it is created in time and is therefore a phenomenon.

However,in order to conclude, form not perceiving a thing for example not seeing it, its non-existence and from perceiving it, for example seeing it, its existence, we have to use other intermediary propositions. 1 Every visible thing, which is not seen in a place, is non-existent in that place and 2. Everything seen in place is existent in that place. But these propositions, irrespective of their truth or falsity are firstly a prior and secondly if we assume their truth and try to prove their validity can be proved only through the laws of causality. That isevery principle in other in order words that we are trying to prove. This, needless to say is a vicious circle and impossible to attain.


As was stated in the definition of philosophy, philosophical propositions explain the characteristics and properties of existence and, rarely, of non-existence and its properties. It was also explained in 3.1 that neither existence, nor nonexistence, nor any of their characteristics, such as necessity, possibility, impossibility, casualty, being an effect, etc., could be experienced or perceived through the senses. Naturally, then, the relationship between existence and it characteristics or non-existence and its properties, which is the subject of philosophical propositions, cannot be understood through the senses or through experience. Therefore, these relationships can be understood only by reason and on the basis of primary selfevident propositions; in other words, it is only by the rational method that we can determine the truth or falsity of philosophical propositions


1- What do we mean by research methodology?

2- Define a priori and a posterior proposition.

3- What is the significance of the fact that posterior propositions are exceptive and a priori propositions are nonexceptive?

4- Why is it that a priori propositions do not allow exceptions?

5- Does every a priori proposition necessarily consist of intangible conceptions? Why?

6- Can we change particular or existential (at least some of them) into universal propositions? If the answer is affirmative explain how? Furthermore, give at least two examples showing such change.

7- Which of the following concepts derive directly or indirectly from sense organs? Why? Movement, possibility, impossibility, body, shape, necessity, existence, nonexistence, water, colour

8- Which of the following propositions are a priori and which are a posterior? Why?

9- Every moving object needs a moving force.

10- Every corporeal body is either black or not black.

11- All acids are sweet in taste.

12- No physical body has a particular colour in itself. It is our eyes that see things in different colours.

13- As long as an observer is looking at an object that object exists. When he stops looking at it, it ceases to exist.

14- Suppose you are given a sheet of paper on which a geometrical shape is printed and three specific lines in the drawing have been highlighted. You are asked to prove that the three highlighted lines in that drawing (and not in general way concerning every drawing with the same characteristics) are equal. Is it possible to prove this point simply by an exact ruler without employing any a priori propositions? Why?

15- Suppose in response to your friend’s invitation you have decided to his house, and you go there. Keeping this supposition in mind, answer the following questions:

1- What a priori propositions must you assume to be true so that your action - your claim to have made a decision to go to your friend’s house and having carried out that decision - appears as reasonable? Mention at least five propositions.

2- Why assuming that these propositions are true is necessary for the rationality of that action?

3- To which types of knowledge does each of these propositions belong?


1- For further explanation, see Majmouah Asar (Collected Works), vol. 6, ‘The Rational Theory’, pp. 332-[^334]:

2- For further illustration, see C.G. Jung, The Fundamental Questions of Philosophy, chapter [^2]:

3- For further information on Verifiability and Falsifiability, see Allen F. Chalmers, The Nature of Science, chapters 1-6; the Open University Press, [^1982]:

4- See Avicenna, Al-Shifa, Al-Tabiyat (Natural Philosophy) (Qum, Library of Ayatullah al-Maraashi al-Najafi, 1404 AH). 3 vols, vol. 2, p. [^53]:

5- Ibid. Pp. 139-[^141]: See also Sadr al-Mutaliheen, Al-Hikma al-Mutaliyah (Transcendental Philosophy) (Beirut: Dar Ihya al-Turath al-Arabiyyah, 1981), 3rd Editon, 9 vols., vol. 8, section 4, chapter 12, pp. 201-204.

[^6]: For further illustration see Collected work vol 6, ‘’ the way of Acquiring Knowledge.’’ pp 245 - 254 See also indi vol 5 The Secondary Intelligible, pp 266 - 292 and also ibidi vol. 10, Epistemo; ogy pp.249 - 305

7- For further illustration see Collected Works vol. The Empirical Theory, pp

8- 334 - 347

9- For another explanation ob the vicious circle see Collected Work Vol 6, pp 683- 684

10- For further explanation see collected work vol 6 pp 478 - [^480]: