Dr Menahem Luz,

Aristotle's Psychological Theory 2

next Summary 3 (On the Soul / De Anima)
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Aristotle's Theory of the Soul

Contents

  1. Early Aristotle on the Soul
  2. Middle Theory of the Soul
  3. Mature Theory of the Soul (Actuality and Potentiality)

    Methodologies for examining the soul

    1. Division by Species
    2. Categories
    3. Matter and Form
    4. The Soul as a Cause
    5. Motion

    6. Bibliography

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    1. Early Aristotle on the Soul

      In fragments of his early dialogue, Eudemus or On the Soul, Aristotle copies Plato's dialectical methodology for investigating the soul. He likewise criticises the Pythagoreans and the harmony of the soul as did Plato.
      However, he also adds that

        that the soul is a specific form (eidos ti)

      Aristotle describes the soul as the form of the living body in De Anima. This seems to be different from the phrase in Eudemus, that the soul is a form simpliciter. In De Anima the soul is not form simpliciter but relatively so to the body on which it depends. Other scholars claim that the phrase in Eudemus is a Platonism:
      • however, the soul is not a form in Plato but an entity between the Forms and the body
      • In Eudemus, Aristotle then conceives the soul as something other than the body and not something belonging to the body
      In discussing the Platonic anti-Pythagorean argument that the soul is not a harmony since harmony has no gradations, Aristotle says in the Eudemus that unlike harmony, the soul has no opposite. This argument is based on the assumption that the soul is a substance which has no opposite either.
      We have here the seeds of an early theory of mind in Aristotle:
      • the soul is a substance (ousia)
      • it is a particularity
      • as such it cannot be suited to any body but to a specific one (an argument raised against transmigration in the De Anima)
      • nonetheless these passages do not hint at the idea of the soul as an actuality of the living body maintained in the De Anima
      • neither do they clearly maintain the dependence of the soul on the body for its existence maintained in the De Anima
      • they even discuss the immortality of the soul although it is unclear if that is to be attacked or maintained in the book

    2. Middle Theory of the Soul

      In the De Anima 2, Aristotle argues that the soul is an actuality of the body but suddenly in lines 413a8-10, he maintains that it is still unclear whether the soul is not really like the captain of a ship

      • this instrumental argument was not discussed previously
      • some have maintained that this phrase is a fragment from earlier versions of the work
      • if it does represent an instrumental stage it would mean
        • that the soul was conceived as separable from the body like the captain from a ship
        • that its function was to rule
        • that its sensation was by help of the body but not by means of it

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    3. Mature Theory of the Soul

      The De Anima 2 opens with a development of a theory of the soul; for this Aristotle proposes two concepts:
      • The soul is the actuality (energeia)of the living (ensouled) body
      • The soul is the completed state (entelecheia) of the living (ensouled) body
      According to this theory
      • the body is matter (hyle) and the soul is its form (eidos)
      • but since the final product -- the completed substance -- is living and changing, the bodily sense and capability is a capacity dynamis
      • the form or soul is the actuality of this movement
      • actuality however can be either an actualised but non-activated state energeia as in possessing knowledge but not thinking of it
      • or it can be the final actualised capabilityentelecheia as in the actual computation of a problem, or the actualised final bloom of a flower
      As an embodied form, the soul cannot be separated from the body
      its senses and sensations are actualised through bodily parts. On the dismantlement of the body, the soul is lost.
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      Methodologies for examining the soul

      1. Diaeresis: Division by Species, genus and difference

        • The method of diaeresis was created by Plato for defining concepts according to their genus, species and differences.
          For Plato this was a means to deduce reality generically and not to induce it from individual objects
        • Speusippus accepted this but went so far as to claim that one could not know any concept unless one could deduce its diaeretic place in the whole of reality
          hence one had to know the diaeresis of all reality to deduce the individual's place in it
        • Aristotle's empirical approach preferred induction and to derive the generic concepts from the individuals which came first
        • these concepts were arranged by genera, species and difference
        • this division could be used to define and classify both living and non-living beings
        • the capacities of a living organism can also be defined and organised diaeretically
        • therefore Aristotle asks on the first page of the De Anima, whether diaeresis is a viable method for enquiring into the soul (402a 20)
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      2. Categories

        Aristotle's categories are not only a method for describing static substances, they are also a method to describe types of movement as in Metaphysics xiii.
        At De Anima 402a 23-26 he asks whether we can define the soul by a division of categories

        • in effect he uses this method along with the others to describe the capacities of the soul
        • its capacity for self-preservation and propagation that is common to all ensouled creatures is directly connected with the soul in the category of substance
        • its capacity for growth and diminution is to be classified as a quantiitve movement
        • its capacity to move is connected with the category of place as a local movement
        • its capacity to feel and sense is connected with the category of qualitative change
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      3. Matter and Form

        Aristotle had worked out a theory of matter (hyle) and form (eidos) in the Physics and Metaphysics.

        • he compares the body to the matter and the soul to the form of the living body
          The De Anima is an extension of this theory to the realm of the animate.
        • In De Anima 2 412b19-25, he compares the soul first to the inanimate axe, the form of the living body is like the sharpness of the axe, there is no differentating between them
        • He also compares it to the part of the body, to the living eye -- the soul is like the sightf of the seeing eye -- when it is deprived of sight, its sight no longer exiss
        • but the living body has many capacities -- that is many facets of actuality and forms -- each one for a special part of the matter
        • the 'soul' in general has no meaning but only a metaphorical one for we should speak of the souls of the body parts
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      4. The Soul as a Cause

        Aristotle had worked out his theory of 4 causes in the Metaphysics.
        See lecture on         Metaphysics 1
        In the De Anima, the soul is a cause of life in the body, but not a material cause like the body, nor an external cause as an efficient cause, but the formal conceptual cause of life in a living body, or sense in a sensing organ. As part of a self-moving organism it is also the final cause of the organisms movement -- eg. the sight is the final cause of the living eyes self-movement.
        In this sense it is both a cause of self-preservation of the whole organism and a cause of sensation and movement in the organism's parts

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      5. Motion

        Aristotle's theory of motion is dependent on his theory of causes and his theory of categoies. Each time of motion can be classified in a separate category of movement. The sou's movement is a self-movement in one of these categories: essential, qualitative, quantitative and place. see above

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        Bibilography for this section

        • G.E.R. Lloyd, Aristotle The Growth and Structure of his Thought (Cam.)
        • A. Gotthelf-J.G. Lennox, Philosophical Issues in Aristotle's Bioglogy (Cam.)
        • R.M. Dancy, 'Keeping Body and Soul Together', in William Wians, Aristotle's Philosophical Development

          for general bibliography see:

        Reading matter for the course.
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