[3.3.6] Ibn Sina on Scientific Method and Demonstration

In the UML Activity Diagram below, I propose a reconstruction of the scientific “business” process based on Ibn Sina’s (Avicenna, 980-1037 AD) ideas about scientific inquiry elaborated in his works Kitāb al-Burhân, Najâh.
Here are some highlights of his ideas:

  • Sense perception with the involvement of the 5 external and internal senses (see [3.3.3]) is the starting point of the scientific process.
  • Abstraction, Induction and Methodic Experience are the activities to acquire First Principles. Syllogisms (see [3.3.5]) and actualization of the Intellect with Forms provided by First Intellect (see [3.3.3], [3.3.4]) both have their roles in these activities.
  • After First Principles are available, new knowledge can be reached with deduction, using syllogisms (see [3.3.5]).
Avicenna on scientific process
Obtain perceptibles of an object with Sense Perception“the universal premises of demonstration and their principles are obtained only through sensory perception…” (McGinnis (2008), cites Avicenna)
ABSTRACTION“by acquiring the phantasmata (خيالات) of the singular terms through the intermediacy of [sensory perception] in order that the intellectual faculty freely acts on them in such a way that it leads to acquiring the universals as singular terms and combining them into a well-formed statement…
[T]he essences perceptible in existence are not in themselves intelligible, but perceptible; however, the intellect makes them so as to be intelligible, because it abstracts their true nature (حقيقتها) from the concomitants of matter…
Thus [the speculative intellect] receives these accidents, but then it extracts them, as if it is peeling away these accidents and setting them to one side, until it arrives at the account in which are common and in which there is no variation and so acquires knowledge of them and conceptualizes them.
The first thing that [the intellect] inquires into is the confused mixture in the phantasm; for it finds accidental and essential features, and among the accidents those which are necessary and those which are not. It then isolates one account after another of the numerous ones mixed together in the phantasm, following them along to the essence. (McGinnis (2008), cites Avicenna)
“this is not Avicenna’s whole story concerning abstraction and acquiring first principles; for as he says later, acquisition of the first principles also involves “a conjunction of the intellect with a light emanated upon the soul and nature from the
agent that is called the ‘Active Intellect’” (McGinnis (2008)).
INDUCTIONAvicenna accepts Aristotle’s view on Induction (see [1.3.8]) however, criticizes it: “Induction has two elements: one involves the sensible content of induction and the other the rational structure of induction, namely, the syllogism associated with induction. If induction is to provide one with the necessary and certain first principles of a science, then the necessity and certainty of the conclusion of an inductive syllogism must be due either to
induction’s sensory element or its rational element or some combination of both. On the one hand, the purported necessity and certainty of induction cannot be known solely through induction’s sensory element; for in good empirical fashion Avicenna
recognizes that necessity and certainty are not direct objects of sensation. On the other hand, if the necessity and certainty are due to induction’s rational component, then the syllogism associated with induction should not be question begging. Yet,
complains Avicenna, in the scientifically interesting cases one of the premises of an induction will be better known than its conclusion, and so the induction is neither informative nor capable of making clear a first principle of a science.” (McGinnis (2008)).
METHODIC EXPERIENCE“Ibn Sînâ’s theory of experimentation is by no means modern, it does move one closer to a modern scientific approach; for it emphasizes both the need to set out carefully the conditions under which experimentation or examination have taken place, as well as the tentativeness of scientific discoveries in the face of new observations…
experimentation involves in part seeking falsifying cases…the exceptions [falsifying cases] would be extremely rare, perhaps observed only once or twice. These rare exceptions might indicate that there is not a causal relation, but they might also indicate that the causal circumstances were more complex than initially supposed…
Experimentation, with its accompanying syllogism, then, occasions certainty…
although experimentation cannot provide “absolute” principles, the natural scientist can use experimentation to discover “conditional,” universal principles, which can function as first principles in a science.” (McGinnis (2003)).
Check certainty condition (true/ real, necessary) “Avicenna’s ‘certainty condition’ (يقين),… includes both being true or real (الحقّ) and necessary (الضروري)” (McGinnis (2008)).
First Priciple AcquiredIf certainty condition is fulfilled.
DEDUCTION“A demonstration according to Avicenna is ‘a syllogism constituting certainty’. In other words, it is a deduction beginning with premises that are certain or necessary that concludes that not only such and such is the case, but that such and such cannot not be the case. Thus, demonstrative knowledge involves possessing a syllogism that makes clear the necessity
or inevitableness obtaining between the subject and predicate terms of its conclusion. In addition, Avicenna divides demonstrative knowledge itself into two categories depending upon the type of demonstration employed. Thus there is the demonstration propter quid, or demonstration giving ‘the reason why’ ( برهان لِمَ ) and the demonstration quia, or demonstration giving ‘the fact that’ (برهان لأن ).” (McGinnis (2008)).


  • McGinnis,  Jon, “Avicenna’s Naturalized Epistemology and Scientific Method”, chapter from: The Unity of Science in the Arabic Tradition: Science, Logic, Epistemology and their Interactions, springer, 2008
  • McGinnis, Jon, “Scientific Methodologies in Medieval Islam”, Journal of the History of Philosophy. 41. 307-327. 10.1353/hph.2003.0033., 2003

First published: 05/09/2019

[1.3.8] Aristotle’s Knowledge/Science Generating Process

In this UML Activity Diagram, I propose a reconstruction of the scientific “business” process using the following Aristotelian (384-322 BC) concepts elaborated in the works Physics, Metaphysics, Posterior Analytics, related to psychology (see [1.3.6]), logic (see [1.3.9]), and scientific inquiry:

  • sense perception
  • observation
  • memory
  • induction (epagôgê)
  • generalization
  • intuition
  • first things (archai) or priori, premise, hipothesis
  • deduction, syllogism (sullogismos ) (see [1.3.9])
  • causation (aition); four causes (material, efficient, formal, final) (see [1.3.4])
  • knowledge (which is about universal, necessary things with identified causes) (epistemê)
Aristotle’s knowledge/science generating process
Activity Action/Description
Careful OBSERVATION• Sense-perception of object
• Store & Recollect the facts
Inference using INDUCTION“it is induction (epagôgê), or at any rate a cognitive process that moves from particulars to their generalizations, that is the basis of knowledge of the indemonstrable first principles of science.” (R. Smith)

• Organize the facts
• Sort out irrelevant facts
• Generalization
• Use bottom-up syllogism
: “there is an induction as a kind of syllogism. We can describe it as a bottom-up syllogism. Induction in this sense means finding out an appropriate middle term where both extreme terms are given” (R. Smith)
• Identify first things (archai; a priori; premise; hypothesis) with the help of intuition
Inference using DEDUCTION“A deduction is speech (logos) in which, certain things having been supposed, something different from those supposed results of necessity because of their being so. Each of the “things supposed” is a premise (protasis) of the argument, and what “results of necessity” is the conclusion (sumperasma).” (R. Smith)
In Aristotle’s model, there is no observational/experimental verification of the knowledge (loop back to the beginning of the process).

• Generate new knowledge using dialectical syllogism
• Identify the Four Causes with demonstrative syllogism (apodeixis):
“The demonstrative syllogism, (apódixis) which produces genuine knowledge, science or epistemé, does not aim to lead from premises to a conclusion up to then unknown. On the contrary, in the demonstrative syllogism, also, the conclusion is an observed fact previously known. The scientific explanation, the reason why, the (dióti), or “cause”, will when found form the premise from which that observed fact can be demonstrated as a conclusion. Thus the scientific syllogism derives facts already known through observation, from reasons why, or archai. It is not a logic of the discovery of new facts, but a logic of proof, of formalizing or systematizing facts already known.” (S. Sfekas)
• Record Scientific knowledge (episteme)

NOTE: This is the first UML Activity Diagram I present on this blog. For modelling business processes there is an alternative standard also in use: BPMN, (Business Process Model and Notation) managed also by OMG.


  • Andersen, Hanne and Hepburn, Brian, “Scientific Method“, The Stanford Encyclopedia of Philosophy (Summer 2016 Edition), Edward N. Zalta (ed.)
  • Galik, Dusan. “Induction in Aristotle’s System of Scientific Knowledge”. Organon F. 13. 495-505., 2006
  • S. Sfekas: Aristotelian Fundamentals of the Practice of Knowledge and Information, conference paper, 2017
  • Shields, Christopher, “Aristotle’s Psychology“, The Stanford Encyclopedia of Philosophy (Winter 2016 Edition), Edward N. Zalta (ed.)
  • Smith, Robin, “Aristotle’s Logic“, The Stanford Encyclopedia of Philosophy (Winter 2018 Edition), Edward N. Zalta (ed.)

First published: 18/04/2019