Aquinas’ Theory of Perception Talk presented at the 19th International Interdisciplinary Seminar What differentiates human persons from animals and machines? Netherhall House, London, 3-1-2017 CONTENT Introduction Hylomorphism: matter and form Acquisition and dealing with information Isomorphism of mind and reality Conclusions Lisska 2016 distinction between esse naturale and esse intentionale It is through the sense impression in the faculty that the sense faculty ‘becomes’ the sense object in the external world, but immaterially or intentionally. The same form is exemplified ‘intentionally’ in the faculty and ‘existentionally’ in the object; this is the Aristotelian insight further enhanced by Aquinas. There is an identity of form, one in esse intentionale and the other in esse naturale, indicating the two modes of exemplification utilized. Without this identity of structure rendered possible by the two modes of exemplification, the isomorphism of mind and reality in Aristotelian ontology and philosophy of mind would be impossible. CONCLUSIONS Hylomorphism is a powerful approach for understanding the full richness of human intellectual capacity. The definition of truth of Aquinas becomes evident truth: adaequatio rei et intellectus truth is the conformity of the intellect to the things. The non-material dimension of the human mind is fully acknowledged. The application of concepts of the metaphysics of Aristotle and Aquinas is a adequate starting point for the study of philosophical issues of modern science.

1. CSR: Culture, Science and Religion Aquina’s theory of perception page 1 3-1-2017

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Content
Introduction
Hylomorphism: matter and form
Acquisition and dealing with information
Isomorphism of mind and reality
Conclusions

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The great problem of human perception
How enter things our mind?
How it is possible that great objects arrive
at microscopic light sensitive cells at the
retina and eventually enter the brain and
the mind.
approach: abstraction
literally: pull something away
next question:
what can be abstracted and what is left?

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Content
Introduction
Hylomorphism: matter and form
Acquisition and dealing with information
Isomorphism of mind and reality
Conclusions

5. CSR: Culture, Science and Religion Aquina’s theory of perception page 5 3-1-2017
the metaphysical analysis of Aristotle
material things:
are physically one,
are metaphysically two:
- the (philosophical) matter
- the form which informs the matter
form of material objects,
- completely matter free,
- is not an object of reality
philosophical matter,
- completely without information
- is not an object of reality
Aristotle, 384-322 BC
matter and forms are principles of beings
- not beings on its own
matter: hyle (literaly wood); form: morphe: philosophy: hylomorphism

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analysis of change by Aristotle
analogy with clay
shapeless clay →head → shapeless clay →vase
clay: on its own shapeless, not determined: matter (hyle)
head, vase: something that determines: form (morphe)
→ Hylomorphism
change:
object I consists of matter and form I
form I passes, form II takes its place
object II consists now of matter and form II

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A modern analogue to material and form
hardware - software
software is always implemented in some hardware,
for example: program file: on punch card
on memory-stick
on CD
on hard-disk
as code written on paper
hardware (switched-on) has always certain information, i.e. software
for example: tv monitor movie
news
tele-text
letters of novel
'snow' if only noise at input
Aristotelian language applied to the material reality:
information, the form, has to be implemented in some kind of hard-
ware, the material, otherwise it is not real, it is virtual, virtual reality.

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the double aspect of reality
philospher material;
what thing is
made of?
information;
how thing is
determined?
what is real? dualism
Platon,
idealists
shadow idea idea weak
Democritus,
atomists
atoms pure
geometry
atoms weak
Aristotle,
realists
matter form,
information
the thing strong
materialists matter chance,
natural laws
matter weak
computer
scientist
hardware software software
implemented
in hardware
strong

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Content
Introduction
Hylomorphism: matter and form
Acquisition and dealing with information
Isomorphism of mind and reality
Conclusions

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acquisition of and dealing with information
as an example: the human eye and the connection with the brain
steps (humans and higher animals):
I: inverse image is formed
II image activates light sensitive cells
III: optic nerve transmits cell signals to cortex
IV: advanced image procession in cortex and
other parts of brain
in each step beyond I:
image is represented by specific molecular states,
i.e. implemented in matter

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acquisition of and dealing with information
what about abstraction?
level I: concepts are formed
example: chair
individual chair:
different forms, materials, changing in time
concept of chair:
constant in time, general
chair: always implemented in matter
science is based on concepts

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acquisition of and dealing with information
what about abstraction?
level II: special concepts are formed
example: concept of circle
individual circle:
different forms, materials, changing in time
concept of circle:
constant in time, general
circle: not always implemented in matter
mathematics is based on concepts not
implemented in matter
increasing abstraction in mathematics
2 apples and 3 apples are 5 apples
2+3=5
a+b=c
a+b=b+a (addition is commutative)

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acquisition of and dealing with information
what about abstraction?
level III: concepts are formed that never
are implemented in matter
example: concept of time, causality,
sein als solches (being as such)
individual time, causality…:
without meaning
concept of time, causality….:
constant in time, general
metaphysics (philosophy) makes
extensively use of concepts never
implemented in matter

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Content
Introduction
Hylomorphism: matter and form
Acquisition and dealing with information
Isomorphism of mind and reality
Conclusions

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isomorphisme of mind and reality
next step in abstraction?
in human mind:
- all information is received from the senses,
- pure information, i.e. the form
- the matter is completely abstracted
first conclusion:
- mind can not be composed of matter
- mind is informed and becomes in certain
sense the observed object
second conclusion:
- object exists: implemented in matter
- and intentionally implemented in mind
Aristotle
Let us now summarize our results about soul, and
repeat that the soul is in a way all existing things.
(De Anima 431b21, trans. Smith)
picture from
http://www.thwink.org/sustain/glossary/Abstraction.htm

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starting point:
material object, consisting of matter and form
in senses and sensory capacities
- matter is more and more removed from the
information
- data processing is carried out
in the mind (with a spiritual dimension)
- the matter-free form is accepted
- and exemplified intentionally
- isomorphism of reality and mind
object: sensory exemplification exemplification in mind
matter (green) and form (red) form and largely reduced matter form without matter
isomorphisme of mind and reality

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distinction between
esse naturale and esse intentionale
It is through the sense impression in the
faculty that the sense faculty ‘becomes’ the
sense object in the external world, but
immaterially or intentionally. The same form is
exemplified ‘intentionally’ in the faculty and
‘existentionally’ in the object; this is the
Aristotelian insight further enhanced by
Aquinas. There is an identity of form, one in
esse intentionale and the other in esse
naturale, indicating the two modes of
exemplification utilized. Without this identity of
structure rendered possible by the two modes
of exemplification, the isomorphism of mind
and reality in Aristotelian ontology and
philosophy of mind would be impossible.
Lisska, 2016
isomorphisme of mind and reality

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some remarks:
the object is not duplicated in the mind
- matter is completely removed from the form
- what left is pure information, and not informed matter
amount of information depends on the receiving mind
- example fir: most recognize evergreen, smell
- only specialist: light harvesting in needle-like leaves
there are two different types of intellectual activities in the mind:
- reasoning, by syllogism, formal thinking, data-procession: also with animals,
computer
- intuition: source of creativity, giving meaning to concepts: only with humans
information allows also to understand behavior and future evolution
- predict trajectory of cannonball
- carry out Gedankenexperiment (mental experiments)
analogy with computational physics
isomorphisme of mind and reality

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Content
Introduction
Hylomorphism: matter and form
Acquisition and dealing with information
Isomorphism of mind and reality
Conclusions

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conclusions
Hylomorphism is a powerful approach for understanding the full
richness of human intellectual capacity.
The definition of truth of Aquinas becomes evident
truth: adaequatio rei et intellectus
truth is the conformity of the intellect to the things.
The non-material dimension of the human mind is fully
acknowledged.
The application of concepts of the metaphysics of Aristotle and
Aquinas is a adequate starting point for the study of philosophical
issues of modern science.

21. CSR: Culture, Science and Religion Aquina’s theory of perception page 21 3-1-2017
This talk has been presented at the
19th International Interdisciplinary
Seminar
What differentiates human persons
from animals and machines?
Netherhall House, London, 3-1-2017