the history and philosophy of thought experiments has attracted considerable attention in recent years. Of particular interest to philosophers as well as historians of science has been the emergence of thought experiments as a common procedure in early modern science, along with the methodological presuppositions that underwrite this practice.1 From a philosophical perspective, the notion of thought experiments is intimately tied in with the much-debated connection between conceivability and possibility, as exemplified by the radical affirmation of the Conceivability Criterion of (...) Possibility by David Hume.2 Consequent upon this, historians of ancient and medieval philosophy have also expressed interest in .. (shrink)

Avicenna's notorious claim that God knows particulars only 'in a universal way' is argued to have its roots in Aristotelian epistemology, and especially in the "Posterior Analytics". According to Avicenna and Aristotle as understood by Avicenna, there is in fact no such thing as 'knowledge' of particulars, at least not as such. Rather, a particular can only be known by subsuming it under a universal. Thus Avicenna turns out to be committed to a much more surprising epistemological thesis: even humans (...) know particulars only in a universal way. (shrink)

Avicenna is a strong proponent of what some of the later ones call qāʻidat al-wāḥid or ‘rule of the one’ (RO). The gist of RO states: from the one only one directly proceeds. In the secondary literature, discussion of this Avicennian rule is usually limited to a particular application of it i.e., the issue of emanation. As result, it’s not really clear what RO means, nor why Avicenna endorsed it. In this paper, I try and remedy this situation by doing (...) two things – one on the taṣawwur front, the other on the tasdīq. First, explain just what the terms of RO amount to – that is, its subject and predicate. In doing this, I distinguish between a narrow and a broad understanding of RO, and the show that, on the Avicennian view, the scope of RO is broad; it is meant to be a general principle of efficient causality. This is why it is appealed to in various contexts to establish substantial philosophical theses. Second, I consider an argument Avicenna offers for RO in the Mubāḥathāt. In unpacking it, I uncover some of its realist presuppositions, and then further clarify it in light of a critique first raised by Bahmanyār and then later made famous by Fakhr al-Dīn al-Rāzī. I then conclude by seeing whether the Avicennian has the resources within the initial premises of the argument to meet the objection that’s raised. (shrink)

God is omniscient; therefore, He knows that ‘the flower in my hand is red.’ If God knows that ‘the flower in my hand is red,’ then He knows it perceptually. God does not know anything perceptually. It is clear that the set of propositions – form an inconsistent triad. This is one of four problems with which Avicenna was engaged concerning God's knowledge of particulars, which I call the problem of perceptual knowledge. In order to solve PPK and three other (...) problems, Avicenna has developed a theory concerning God’s knowledge of particulars. Secondary literature around Avicenna’s theory of God’s knowledge of particulars has mostly directed its attention to give an account of Avicenna’s positive theory rather than the problems which that theory was designed to solve. But this paper will not do the same thing as this secondary literature. In contrast, in this paper, I will concentrate on the characterization of one of the problems, i.e., PPK, because of which Avicenna has presented his positive theory of God’s knowledge of particulars. In short, this paper aims to show why Avicenna deems explaining God’s knowledge of, say, the redness of a flower, via his accepted theory of perception as problematic. In this regard, I will extract three versions of PPK based on Avicenna's philosophy and through it will shed some light on Avicenna’s theory of God’s knowledge of particulars. (shrink)

(i) God is omniscient; therefore, for any change, C, among particulars, God knows the occurrence of C. (ii) If God knows the occurrence of C, then X. (iii) not-X. It is clear that the set of propositions (i)—(iii) is inconsistent. This is the general form of two problems—which I call the ‘problem of change in knowledge’ (PCK) and the ‘problem of change in essence’ (PCE)—for Avicenna concerning God’s knowledge of particulars. No work in the secondary literature has discussed exactly what (...) PCK and PCE are. In this paper, I will clarify exactly what they are. (shrink)

The term “principle of sufficient reason” (PSR) was coined by Leibniz, and he is often regarded as its paradigmatic proponent. But as Leibniz himself often insisted, he was by no means the first philosopher to appeal to the idea that everything must have a reason. Histories of the principle attribute versions of it to various ancient authors. A few of these studies include—or at least do not exclude—medieval philosophers; one finds the PSR in Abelard, another finds it in Aquinas. And (...) while Leibniz retains pride of place in these histories, Spinoza is sometimes said to precede him “in appreciating the importance of the Principle and placing it at the center of his philosophical system.” In this paper, the author argues that the same should be said of the Islamic philosopher Avicenna. Writing 600 years before his early modern counterparts, Avicenna routinely and consistently appeals to the PSR in generating his metaphysical system. The paper aims first to establish that Avicenna deserves a position of prominence in histories of the PSR, and then to consider how he addresses certain challenges to the PSR, especially the threat posed by necessitarianism. (shrink)

Ancient commentators like Ammonius and Boethius tried to solve Aristotle's “sea battle argument” in On Interpretation 9 by saying that statements about future contingents are “indefinitely” true or false. They were followed by al-Fārābī in his commentary on On Interpretation. The article sets out two possible interpretations of what “indefinitely” means here, and shows that al-Fārābī actually has both conceptions: one applied in his interpretation of Aristotle, and another that he is forced into by the problem of divine foreknowledge. It (...) also explains the relevance of al-Fārābī's remarks as a link between the non-statistical modal theories of Philo and Avicenna. (shrink)

Name der Zeitschrift: Archiv für Geschichte der Philosophie Jahrgang: 97 Heft: 2 Seiten: 160-195.

Avicenna's discussion of space is found in his comments on Aristotle's account of place. Aristotle identified four candidates for place: a body's matter, form, the occupied space, or the limits of the containing body, and opted for the last. Neoplatonic commentators argued contra Aristotle that a thing's place is the space it occupied. Space for these Neoplatonists is something possessing dimensions and distinct from any body that occupies it, even if never devoid of body. Avicenna argues that this Neoplatonic notion (...) of space is untenable on the basis of three arguments. In general he maintains that bodies' impenetrability is explained by reference to dimensionality. Consequently, if it is dimensionality that explains impenetrability, and yet as the Neoplatonists hold space inherently possesses dimensions, material bodies could never interpenetrate space and so occupy it and thus bodies could never have a place. The conclusion is patently false. In additions Avicenna argues that the method used to arrive at the possibility of space is illicit, and so Neoplatonist cannot show that space is even possible. Thus, concludes Avicenna, Aristotle's initial account must be correct. The paper outlines the historical context of this debate and then treats Avicenna's arguments against space in detail. (shrink)