[5.0.2] John Philoponus on Cosmology

John Philoponus (490-570 AD) implemented several basic modifications to the Aristotelian cosmology:

  • Sublunary bodies, celestial bodies, and the Universe are objects with form.
  • Celestial bodies are components of the universe, located in celestial spheres.
  • Substance has impetus.
  • Elements, like air, fire, water, and earth are subquantityes of substance.
  • Aether and Unmoved Mover are not part of the Philoponus model of ([1.3.14] Aristotle on Cosmology)

The following OntoUML diagram shows the main classes in this model:

Philoponus cosmology

ClassDescriptionRelations
ObjectObjects, according to Aristotle are primary existents, compounds of Substance (matter) and Form.
FormThe form is that which unifies the substance into a single object, and which provides actuality. characterizes Object
SubstanceThe substance is that which persists in the object, and which provides potentiality. Substance at the bottom level, is composed of a mix of the four elements, is generated and corruptible.
Impetus “So far, Philoponus’ applications of impetus theory are only dynamics into unconnected areas. Projectile motion was explained air. The heavens were thought to be alive and their motion, explained in psychological terms. The fall of rocks and rising by reference to an inner nature, while the rotation seen, was a special case. Philoponus’ next move has the effect context is the discussion of creation in the book of Genesis. opificio mundi, which has been dated to thirty or forty extends impetus theory, in one form or another, to all the to do so by the belief, for which he has argued in so many the universe. It is God who implants (< entheinai ) a motive sun, moon and other heavenly bodies at the time of creation. downward inclination (rhopê) in earth and the upward inclination implants in animals the movements which come from the souls The impetus which God implants in heavenly bodies seems which a thrower implants in a javelin, but in the other cases, impetus implanted in the elements, earth, air, fire and water, in Philoponus’ view, elements lose their weight or lightness, move down or up, once they reach their proper places. when lifted away from its resting position. What God implants inclination to move down, but an inclination to move down, animals, what God implants when he implants their impetus in a javelin, and indeed at this point the analogy I have been insisting that, in so far as Philoponus unifies creator God which enables him to do so.” (Sorabji, 2020)
Universe “in the De caelo Aristotle treats of the universe as a single individual substance [object] with form and matter… ‘Since the universe is perceptible, it is an individual thing [object]; for every perceptible thing exists in matter…
Aristotle’s assertion, in De caelo 1. 9, that the universe is individual occurs in the context of his rejecting the atomist’s many-worlds thesis: ‘Such a plurality is impossible if this world is made from the entirety of matter, as it is’. In general, form admits of plural instantiations, he concedes. However, when a form is instantiated in all matter, it can be instantiated only once.” (Matthen, 2001)
subkind of Object
Celestial BodyCelestial Bodies are the stars, the planets, the Sun, and the Moon. subkind of Object; component of the Universe; located on CelestialSphere
Celestial sphere The Celestial Bodies, are located on the (perfect) celestial spheres. The stars are fixed on their own sphere; each planet, the Sun and the Moon circulates on its own sphere. This movement is circular, regular and continuous
Sublunary body Sublunary bodies are located under the Celestial Sphere of the Moon. They include the Earth – the center of the universe, ad all the natural (e.g. minerals, living beings, humans) and man-made objects (e.g. houses, statues) on the Earth.subkind of Object; component of the Universe
ElementAristotle believes that everything is made of earth, air, fire and water. These elements are defined by their possession of one of each of the two fundamental pairs of opposites, hot/cold and wet/dry. Aristotle also thinks that these elements can change into one another” (Ainsworth, 2016)subquantity of substance
Water; Earth; Fire; AirAristotle believes that everything is made of earth, air, fire and water. These elements are defined by their possession of one of each of the two fundamental pairs of opposites, hot/cold and wet/dry. Aristotle also thinks that these elements can change into one another” (Ainsworth, 2016)subkinds of Elemenet

Sources

  • SORABJI, RICHARD: “HILOPONUS AND THE REJECTION OF ARISTOTELIAN SCIENCE”, EDITED BY RICHARD SORABJI INSTITUTE OF CLASSICAL STUDIES SCHOOL OF ADVANCED STUDY UNIVERSITY OF LONDON 2010
  • Wildberg, Christian, “John Philoponus”The Stanford Encyclopedia of Philosophy (Winter 2021 Edition, Edward N. Zalta (ed.)
  • Ainsworth, Thomas, “Form vs. Matter“, The Stanford Encyclopedia of Philosophy (Spring 2016 Edition), Edward N. Zalta (ed.)
  • Bodnar, Istvan, “Aristotle’s Natural Philosophy”The Stanford Encyclopedia of Philosophy (Spring 2018 Edition), Edward N. Zalta (ed.)
  • Matthen, Mohan,The Holistic Presuppositions of Aristotle’s Cosmology”, in Oxford Studies in Ancient Philosophy 20:171-199 January 2001

First published: 19/8/2022

[4.15.9] John Duns Scotus on Logical Possibility and Possible Worlds

John Duns Scotus (the “Subtle Doctor,” 1265/66–1308 AD), in “Ordinatio” writes about modal theory, logical possibility, and how these concepts influence the state of affairs in the world. According to his ideas:

  • God’s divine intellect includes all the simple notae, which are necessary and true propositions, like logical, mathematical, metaphysical truths.
  • Logical possibility is a non-repugnant or non-contradictory relation between two (or more) simple notae. E.g., the simple notae “animality” and “rationality” are non-repugnant since together define “man”.
  • The simple notae related by logical possibility are combined in the divine intellect in contingent divine ideas. E.g., “man”
  • Some divine ideas are necessary and true by definition; these are the necessary propositions. E.g., a priori truths, like “A triangle has three angles.” Others are contingent, with undefined truth value; these are contingent propositions.
  • The divine intellect presents the contingent propositions to the divine will, which decides for some of them by making them true, and with the same act creating them in the world. These are the true propositions. It is noteworthy that the freedom of the divine will is limited to the realm of the contingent propositions.
  • The maximal consistent collection of all the true propositions describes possible worlds, from which one is our real world.

The following OntoUML diagram presents Duns Scotus’s theory of logical possibility and possible worlds:

Duns Scotus’s theory of logical possibility and possible worlds

ClassDescriptionRelations
DivineIntellectGod’s intellect
DivineWill “The divine intellect presents these contingent propositions to the divine will as not yet having a truth value, and the divine will then (in a second instant of nature) contingently determines each to be true or be false.” (Normore, 2003)

“Since God’s [divine] will is the only root of contingency, it follows that ideas necessarily have their content and cannot ground a representation of contingent states of affairs. Conversely, suppose that God’s knowledge of future contingents were based on ideas, then he would not be omniscient, for he would know that Socrates could be either sitting or standing up at T, not that he is sitting at T. Finally, there would be no more difference between God’s knowledge of what is actual and of what is simply possible.” (Anfray 2014)
presents contingent propositions to DivineWill
SimpleNotae“The first stage is God’s natural knowledge of all necessary propositions. These are logically simples and are sometimes called by Scotus [simple] notae. Such notae are related to others according to repugnance or compossibility, independently of any power to bring them about. However, they are not self-subsistent entities, but are the products of God’s intellectual activity, which thus endows them with an ontological status, as intelligible beings. But the logical and modal properties of these entities are not constituted by God’s intellectual activity. Scotus summarizes this by claiming that the possibilia are formally such from themselves (formaliter ex se), but “principially” from God (principiative ab eo). All logical, mathematical, and metaphysical truths, in general all necessary truths, are known at precisely the instant when God produces, thinks things, and produces them in an esse intelligibile. Moreover, since the relations of compossibility [non-repugnance] and repugnance are independent from God’s intellectual activity, any modal truth is necessarily so. This entails that anything possible is necessarily possible.” (Anfray 2014) shared part of DivineIntelect Possibility and DivineIdea
LogicalPossiblityFor Scotus logical possibility is a fundamentally relational idea: “We can intelligibly speak of it only when we are dealing with several notae. Similarly, we can only ask whether notae are consistent when we are dealing with more than one. Thus, in the typical cases the question of whether some possible is possible of itself reduces to the question of the status of a relation among its metaphysical constituents: Are they related of themselves, and in what sense does that relation presuppose its relata?”
Simple notae are true and necessary.
relates between SimpleNotae; defines DivineIdea
Non-repugnance“Scotus articulated a notion of logical possibility as the nonrepugnance of terms and claimed that there is a real power corresponding to every logical possibility.” (Normore, 2003)

We can understand the concept of non-repugnance as the contratry of repugnence: the concept of ‘chimera’ is internally incoherent in the sense that the metaphysical constituents out of which the common nature of chimera would be composed (the notae) simply cannot be combined, and that is why there is a further repugnance between ‘chimera’ and ‘being something’. But this repugnance presupposes that ‘chimera’ is itself a complex term in which several notae are combined.Achimera is perhaps an animal with the head of a lion, the body of a goat, and the tail of a serpent. These notae are themselves complex and could be analyzed in the same way. On Scotus’s view, we eventually reach simple notae. Suppose we ask then whether all simple notae are possible – and further, whether they are possible of themselves.” (Normore, 2003)
characterizes LogicalPossibility
DivineIdea“According to Scotus, all combinations of compatible [non-repugnant] notae are objects of God’s knowledge, which he calls also [divine] ideas. Scotus is less explicit on the content of ideas than on their ontological status, but it is likely that an idea is an intellectual representation of any object, either of an individual like ‘Socrates’ or of a common nature like ‘man’ and that it contains everything that can be grasped by God through his intellect alone. An idea would be something like the deductive closure of all necessary truths concerning a given object. For instance, God’s intellect produces the notae of animality and rationality and these, being intrinsically nonrepugnant, can be combined in a single subject, man. And man can be combined with an individual differentia to produce a possible individual, say ‘Socrates.’ The idea of Socrates contains all the properties grounding necessary truths concerning him: that he is a man, that he is a rational animal, and that it is possible that he is sitting at T, and so on. However, it does not include the property of sitting at T, because it is a contingent truth. This leads Scotus to reject theories that ground God’s knowledge of future contingents on his ideas. First, they can ground only analytical, thus necessary truths. Moreover, ideas are intellectual representations, excluding any volitional element. They are therefore purely natural occurrences in God’s mind.” (Anfray 2014)
Necessary Proposition“Scotus has as a basic notion in his modal picture that of a nonepugnant collection of notae. Second, he claims that having thought the notae, the divine intellect naturally and in a single instant of nature considers all nonrepugnant combinations of them. Some of these combinations are such that it would be repugnant for their elements not to be so combined. These correspond to necessary propositions.” (Normore, 2003)
Necessary propositions are true and necessary.
subkind of DivineIdea; shared part of DescriptionOfPossibleWorld
ContingentProposition“Scotus has as a basic notion in his modal picture that of a nonepugnant collection of notae. Second, he claims that having thought the notae, the divine intellect naturally and in a single instant of nature considers all nonrepugnant combinations of them. […] Others are such that it is not repugnant for their elements either to be so combined or not. These correspond to contingent propositions.” (Normore, 2003)
Contingent propositions are contingent and have undifined truth value.
subkind of DivineIdea; shared part of DescriptionOfPossibleWorld
TrueProposition“The divine intellect presents these contingent propositions to the divine will as not yet having a truth value, and the divine will then (in a second instant of nature) contingently determines each to be true or be false. The divine will thus contingently determines a maximal consistent collection of contingent propositions to be true. Such a maximal consistent collection of [true] propositions is a description of (or, on some views, is) what both Leibniz and twentieth-century modal theorists would call a possible world.” (Normore, 2003)
True propositions contingent and true.
subkind of ContingentProposition; shared part of DescriptionOfPossibleWorld; defines and creates Thing
ThingAn object, a substance, a state of affairs in a possible world.exclusive part of PossibleWorld
DescriptionOfPossibleWorld “The divine will thus contingently determines a maximal consistent collection of contingent propositions to be true. Such a maximal consistent collection of [true] propositions is a description of (or, on some views, is) what both Leibniz and twentieth-century modal theorists would call a possible world.” (Normore, 2003) defines PossibleWorld
PossibleWorldA possible world, our world is an instance of that.

Sources

  • Normore, Calvin G., “Duns Scotus’s Modal Theory”, The Cambridge Companion to Duns Scotus, Cambridge University Press 2003, ed. Thomas Williams
  • Anfray, Jean-Pascal Anfray, “Molina and John Duns Scotus”, A Companion to Luis de Molina, Brill, 2014
  • Williams, Thomas, “John Duns Scotus“, The Stanford Encyclopedia of Philosophy (Winter 2019 Edition), Edward N. Zalta (ed.)

First published: 27/5/2021