Knowledge in Medieval Philosophy

Henrik Lagerlund, Henrik Lagerlund

• Publisher: Bloomsbury Academic
• Year: 2021
• ISBN:
  9781474258319
• Edition: 1
• Topic: Philosophie
• Subtopic: Epistemologie in der Philosophie

To know epistemology's history is to know better what contemporary epistemology could be and perhaps should be – and what it need not be and perhaps ought not to be. Knowledge in Medieval Philosophy covers the influence of Aristotle and Augustine during the Middle Ages. Epistemology and scepticism is part of philosophy from the late thirteenth century onwards, and knowledge was of great philosophical concern throughout the Middle Ages. By putting the medieval discussion in context it contributes to shedding light on the era and its thinkers, as well as to making it relevant for contemporary epistemologists. Demonstrating important aspects of epistemology, ones that has huge importance for our everyday life, chapters cover the notion of testimony and thinkers such as Avicenna, Scotus amd the definition of knowledge found in Ockham.

1

Avicenna on Knowledge

Deborah L. Black

1. Introduction

Avicenna’s epistemology is primarily framed around the theory of knowledge or science put forward in Aristotle’s Posterior Analytics. But Avicenna also introduced a number of novel elements into his epistemology, some of which were the result of earlier developments within the Islamic world, while others reflect his personal philosophical commitments and concerns. The most significant developments among his predecessors can be traced back along two main lines. The first leads to the founder of Islamic Aristotelianism, the so-called second teacher, Al-Fārābī (870–950), who established what became the paradigm for understanding the nature of philosophy and its relation to religion along largely epistemological lines. Taking his cue from certain peculiarities in the Arabic translation of the Posterior Analytics, Fārābī identified philosophy as the path to certain knowledge (ʿilm yaqīnīy), contrasting philosophical certitude with the lesser epistemic states produced by various other sources and methods, including those employed by religion, law, and theology. Following him, Avicenna, too, focused his epistemological discussions on the topic of certitude and its relation to lesser epistemic states. The second line of influence on Avicenna comes, somewhat ironically, from the main intellectual rivals of the Islamic philosophers, the rational theologians or mutakallimūn. A characteristic feature of the theologians’ method was to begin their treatises with a discussion of the nature and principles of knowledge. While Avicenna often criticized the details of this kalām epistemology, he nonetheless incorporated some of its epistemological categories into his own treatises on demonstration. As a result of this critical appropriation of his rivals’ views, Avicenna developed new lines of epistemological enquiry that were largely foreign to the Aristotelian tradition itself, such as his account of testimony as a legitimate source of knowledge, and his recognition of the epistemic value of introspection.

2. Two types of knowledge: conceptualization and assent

Like most philosophers within the Aristotelian tradition, Avicenna (1952: 16–17) pursued most of his epistemological theorizing within his logical works, since logic was generally viewed as an instrumental science whose ultimate goal was to produce knowledge of the unknown:

Since the perfection of human beings, insofar as they are humans possessed of an intellect ... consists in their knowing the truth for its own sake, and the good for the sake of doing it and acquiring it; and [since] the first and inborn nature (al-fiṭrah al-ūlā wa-al-badīhah) of human beings on its own is of little help in this, because most of the knowledge that is attained by them only comes through acquisition (bi-al-iktisāb); and [since] what causes the unknown to be acquired is what is known – it is necessary that human beings first begin to know how they can acquire the unknown from the known.¹

In this account of the epistemological function of logic, Avicenna appeals to a distinction drawn from his theological rivals, between natural or innate knowledge (ʿilm badīh) on the one hand – which the mutakallimūn also describe as ‘necessary’ (ḍarūrīy) – and acquired knowledge (ʿilm muktasab) on the other.² Avicenna uses this distinction to set up another important dichotomy in his theory of knowledge, between conceptualization or concept-formation (taṣawwur) and assent (taṣdīq).³ Conceptualization and assent are the two basic kinds of knowledge that are available to human knowers: each type of knowledge is reducible to a set of basic principles, and the principles of assent can themselves be analyzed into concepts. The distinction between conceptualization and assent is not Aristotelian, but from al-Fārābī onwards it becomes the standard framework for discussions of knowledge and the logical tools that produce knowledge.⁴

Conceptualization is the basic capacity of the mind to conceive the nature or quiddity (māhiyyah) of something, such as that of ‘humanity’ or ‘triangularity’ (Avicenna 1985: 43; trans. Ahmed 2011: 3, §1). One can conceive of such a quiddity without any corresponding act of assent: I can think about a triangle without affirming or denying that triangles exist, or that they have certain properties. Assent, however, presupposes the prior act of conceiving that to which one assents. The key characteristic of assent is that it involves a judgement that some proposition, p, is either true or false. Avicenna sometimes frames this as a judgement regarding the correspondence between what the proposition asserts and the way things exist outside the mind: ‘Assent causes the relation (nisbah) of [the conceived] form to the things themselves which correspond to it to arise in the mind. And falsification does the reverse of this.’ For this reason, not everything that is complex or propositional in form involves assent; rather, all mental acts that do not involve a judgement of truth or falsity are classified as acts of conceptualization by default. For example, the mental act that corresponds to a command such as ‘Do this!’ counts as conceptualization on Avicenna’s (1952: 17) account; and even a statement such as ‘Every white is an accident’ can be merely conceptualized if, for example, one doubts whether it is true or false (cf. 1985: 97).⁵ From an epistemological perspective, however, Avicenna’s main interest is in the conceptualization of quiddities, since these form the building blocks out of which assent may be constructed. The main logical tool that is used to produce new acts of conceptualization on the basis of previously known concepts is the definition; to acquire new acts of assent, one employs various inferential methods, in particular – as one might expect from an Aristotelian – syllogisms.

3. Meno’s paradox and the principles of knowledge

Avicenna holds that complex acts of both conceptualization and assent can ultimately be reduced to simpler acts which we grasp immediately. These are the ‘known’ things from which the search begins for what is unknown. Avicenna links this foundationalist structure of knowledge to the resolution of the paradox of inquiry, once again following the lead of his predecessor Fārābī. This famous paradox, raised by Meno in Plato’s eponymous dialogue, asks how it is possible to learn anything anew – to arrive at what is unknown from what is known.⁶ If we don’t know the thing that we are seeking, then we won’t recognize it when we find it; if we are able to recognize it, then it seems that it was not really unknown to us. Avicenna illustrates what is at stake in this paradox with an example drawn from the paraphrase of the Posterior Analytics by the Greek commentator Themistius (c. 317–88): ‘This is akin to one who seeks a runaway slave he does not know. If he finds him, he would not recognize him’ (Avicenna 1956: 74; trans. Marmura 2009: 55).⁷ Avicenna resolves the paradox by appealing to the distinction between conceptualization and assent. He admits that if something is totally unknown to us, we are not in a position to seek it. But there are many different kinds of unknown things: some are unknown conceptually, whereas others we may have conceived, without having yet assented to any claims about them. Using the example of the runaway slave, Avicenna points out that we might know his escape route and have a description of some identifying mark that will allow us to recognize him when we find him. These items of knowledge will be akin to prior conceptual knowledge; by the same token, as we embark on our search, we will also pick up additional clues through observation and inference that will aid us in apprehending him. For Avicenna, then, the answer to Meno’s paradox is to recognize that conceptual knowledge already contains potentially the assentive knowledge that is built upon it; so long as we are not without prior concepts, we will be able to escape the dilemma as posed by Meno.

Since Avicenna does admit that we cannot seek what is entirely unknown to us, the adequacy of his solution depends upon rejecting the possibility that we could ever be completely lacking in conceptual knowledge. Plato had posited the theory of recollection as a way to account for the soul’s latent possession of pre-existent knowledge, but Avicenna argues that this is a defeatist position which ‘acquiesces to the doubt’ posed by Meno by pushing the act of acquisition into a previous existence of the soul. The correct solution is instead to recognize the existence of primary items of both assentive and conceptual knowledge that arise naturally, without our ever being aware of our ignorance of them (Avicenna 1956: 75–6; Marmura 2009: 57–9). As Avicenna remarks in The Deliverance, the syllogisms that produce assent and the definitions that produce concepts are divisible into parts which are in turn assented to (the premises) or conceived (the terms). But since ‘this cannot go on to infinity, so that knowledge of these parts is only attained through the acquisition of other parts, whose nature is to proceed to infinity’, Avicenna (1985: 97) argues that all knowledge must ‘terminate in something which is assented to and conceived without any intermediary’ (cf. Ahmed 2011: 87–8).

4. Primary concepts

In his logical works, Avicenna generally focuses his attention on the primary propositions that are the foundational acts of assent. For an account of the primary concepts we must look instead to the Metaphysics of the Healing, Book 1, chapter 5. There, Avicenna (2005: Bk. 1, c. 5, 23, §4) reprises his argument against an infinite regress on the conceptual level: ‘If every conception were to require that [another] conception should precede it, then [such a] state of affairs would lead either to an infinite regress or to circularity.’ Avicenna identifies a small number of primary concepts, of which the two most important are that of ‘the existent’ (al-mawjūd) and ‘the thing’ (al-shayʾ), the latter of which he identifies with essence or quiddity. To these, Avicenna adds the modal concept of ‘the necessary’ (al-ḍarūrīy), and the concept of ‘the one’ (al-wāḥid). These concepts, he says, are ‘impressed in the soul in a primary way’: that is, they are the most basic concepts we have, and they cannot be analysed into any simpler, prior notions upon which they depend for their comprehension. They are instead ‘conceived in themselves’, and thus serve as the ‘principles’ (mabādiʾ) for all other concepts. By this, Avicenna seems to mean that these concepts are implicitly presupposed whenever we entertain more complex concepts: we cannot understand any other concepts at all unless we implicitly understand them as the concepts of existent things, that is, beings possessing some determinate essence or nature. For example, as soon as I acquire the concept ‘cat’, I implicitly conceive an existent thing, that is, a being with a feline essence. That does not mean, of course, that I explicitly formulate the abstract metaphysical concepts of essence and existence; it means that to conceive a cat is already to have the concepts of ‘existent’ and ‘thing’.⁸ This entails that the primary concepts cannot be defined, since they have no parts; moreover, we should not need to define them, since, as primary, they are naturally known to all human beings who have any concepts whatsoever. Still, that knowledge may be merely implicit and unconscious, or confused. In such cases, one...