Internal Faculties, Reason and the Five External Senses

1. The Next Stage in the Sources of Knowledge

The principal means of created knowledge have already been identified as sound senses, truthful report and reason. The discussion now asks where mental images, imagination, recollection, experience and inward awareness fit within that scheme.

The issue is not whether people imagine and remember. It is whether these operations should count as independent, authoritative means of obtaining knowledge, or as modes of sensory and intellectual activity.

Recalling an absent person's face differs from knowing that the person is presently at home. The first concerns memory; the second requires appropriate evidence. This distinction guides the treatment of the inner faculties.

2. What Counts as an Independent Source of Knowledge

مُسْتَفَادًا مِنَ الْخَبَرِ الصَّادِقِ، جَعَلُوهُ سَبَبًا آخَرَ
Something derived from truthful report was treated as another cause.

When classifying sources of knowledge, one asks what ultimately warrants a claim. A conclusion may depend on reliable testimony even when further scholarly reasoning is involved.

For instance, a legal principle may be known through an authenticated report and then applied to a specific case through inference. The report supplies a premise, while reason performs the inference. Naming these activities separately does not establish two entirely new basic sources.

We must distinguish a source of information from a way of deriving a conclusion from that information.

3. Inner Faculties: What Is Actually Disputed

وَلَمَّا لَمْ يَثْبُتْ عِنْدَهُمُ الْحَوَاسُّ الْبَاطِنَةُ
For them, the inner senses had not been established in the proposed sense.

Some philosophers explained mental operations through distinct internal faculties located in parts of the brain. The text does not accept those faculties as additional, independently established means of knowledge, since their precise existence and character were considered unproven.

Remembering, imagining and judging are recognizable human activities. Claiming that each requires a separate bodily organ or faculty is a further philosophical hypothesis.

Observing an operation does not by itself prove every detail of the supposed inner mechanism. The dispute concerns the explanation, not the everyday reality of thinking or remembering.

4. The Five Inner Faculties in Classical Psychology

Classical philosophical psychology commonly distinguishes five inner faculties: common sense, imagination, estimation, memory and the compositive faculty. They were invoked to explain how perceptual forms are gathered, retained and recombined, and how particular meanings are apprehended.

Common sense: integration of inputs from external senses.
Imagination: retention of sensible forms after objects disappear.
Estimation: grasping particular meanings not directly sensed.
Memory: retaining such particular meanings.
Compositive faculty: combining or separating stored representations.

This is a historical philosophical model, not an established map of the modern brain.

5. Common Sense and the Unity of Perception

الحِسُّ الْمُشْتَرَكُ
The hypothesized faculty in which perceptions from the external senses are gathered.

We see a fruit, touch it and smell it. These experiences differ, yet we understand them as belonging to one fruit. Classical psychologists assigned this integration to a faculty called common sense.

The eye supplies visual qualities, touch supplies texture and the nose supplies odor. Recognizing the same object across these presentations introduces a further cognitive relation.

The example explains the question of how many sensory inputs form one experience; it does not independently demonstrate the existence of a separately located inner sense.

6. Imagination and Retained Sensory Forms

الْخَيَالُ
Retention of a perceptual form after the sensible object is no longer present.

After seeing a familiar face, one may recall its appearance when the person has left. The classical classification associates such retention with imagination.

The survival of a mental image is not the survival of the external object before our senses. Remembering a past scene does not show that it is still occurring.

An image may support understanding or recollection, but claims about an external situation require suitable independent evidence.

7. Estimation and Particular Meanings

الْوَهْمُ
The proposed faculty that apprehends a particular meaning associated with sensed objects but not directly sensed as a color or sound.

One classical example concerns recognizing friendliness or hostility from another person's behavior. Such relations are not sensed in the same way as color, though we may infer them from circumstances.

The technical term wahm (estimation) does not simply mean a false delusion here; it names a theory of particular non-sensible significance.

An expression or gesture alone does not justify certainty about another person's intentions. The force of the evidence and the possibility of error must be assessed separately.

8. Memory and Imagination: Different Objects of Retention

In the classical account, imagination stores sensible forms, whereas memory retains particular meanings attributed to estimation. Both involve retention, but the kind of retained material differs.

Form: a person's face or distinctive voice.
Meaning: recollection of a person's kindness and the trust once associated with it.

A remembered impression may help explain past experience without being sufficient to judge the person's current conduct.

The underlying dispute is whether these processes establish a distinct inner faculty, or whether the names describe different functions of cognition.

9. The Compositive Faculty and Mental Recombination

الْمُتَصَرِّفَةُ
The proposed faculty that combines or separates available mental forms and meanings.

A person may combine familiar parts into an imagined creature never encountered in reality, such as a human with two heads. Forming that image does not establish that such a creature exists outside the mind.

Conceivability and external existence are different. The ability to imagine a composite demonstrates a cognitive operation, not the reality of every imagined object.

This distinction preserves the usefulness of imagination while resisting an invalid inference from a mental construction to a fact about the world.

10. Why the Separate Inner Faculties Are Challenged

One objection to this classification is that the distinct activities attributed to separate faculties might be different operations of a more general cognitive capacity. Merely distinguishing the retention of forms from the retention of meanings does not prove that each requires a separate bodily faculty.

Likewise, the premise that one faculty can perform only one kind of operation itself needs justification. Without it, plurality of functions does not establish plurality of organs.

A student can read Arabic, understand its meaning and remember it. These are distinguishable activities, but that fact alone does not establish a unique physical organ for each.

The criticism addresses a philosophical account of faculties, not the occurrence of perception or memory.

11. Reducing the Modes of Knowing to Reason

وَكَانَ مَرْجِعُ الْكُلِّ إِلَى الْعَقْلِ
All of these were ultimately referred back to reason.

Another account treats imagination, experience, intuition and similar mental acts as modes of rational operation rather than additional independent basic sources. Reason has a central role in connecting meanings and forming judgments.

Repeated observation provides material, while deriving a general principle requires inference. Thus sensation and reason may contribute to the same conclusion.

Calling reason foundational does not entail that no sensory experience can occur without an explicit syllogism. The issue concerns classification of epistemic sources and cognitive operations.

12. Self-Evident, Experimental and Intuitive Knowledge

الْحَدْسِيَّاتُ وَالتَّجْرِبِيَّاتُ وَالْبَدِيهِيَّاتُ وَالنَّظَرِيَّاتُ
Self-evident, experimental, intuitive and inferential cognitions.

A self-evident judgment is recognized upon grasping the relevant terms. Experience joins observations to reasoning; intuition apprehends a connection swiftly; deliberate inference arranges premises to reach a conclusion.

These labels need not refute the three broad sources of knowledge: empirical material may come from the senses while reason establishes or evaluates a broader conclusion.

Feeling heat from one fire is a particular observation. Forming a dependable general claim about heat requires a further warrant. A quick impression should not be conflated with a justified universal judgment.

13. Experience Is More Than One Observation

الْفَرْقُ بَيْنَ الْحِسِّ وَالتَّجْرِبَةِ
The difference between immediate sensation and experience.

Perceiving an event once is a sensory occurrence. Experience often involves repeated observations, attention to circumstances and reflection on how outcomes are connected.

If one patient improves after taking a remedy, that is an observation, not by itself a reliable universal claim. Alternative explanations and further evidence matter.

Classical discussions recognize experiential knowledge, but its acquisition can involve both sensation and reason. Accordingly, it need not be counted as a wholly separate fourth foundational source.

14. The Five External Senses

فَالْحَوَاسُّ جَمْعُ حَاسَّةٍ بِمَعْنَى الْقُوَّةِ الْحَاسَّةِ
“Ḥawāss” is the plural of a faculty of sensing.

Five outward senses are distinguished according to their characteristic objects: hearing, sight, smell, taste and touch. Each has an appropriate field of perception.

Hearing — sounds.
Sight — light, colors, shapes and visible motion.
Smell — odors.
Taste — flavors.
Touch — heat, cold, texture and related qualities.

A sense should not be assumed to apprehend all the objects of another sense. The following discussion examines the traditional accounts of their organs, objects and operation.

15. Hearing: Faculty, Sound and Reception

السَّمْعُ وَهِيَ قُوَّةٌ مُودَعَةٌ فِي الْعَصَبِ الْمَفْرُوشِ فِي مَقْعَرِ الصِّمَاخِ
Hearing is described as a faculty placed in a nerve associated with the inner ear.

The special object of hearing is sound. The passage uses a classical bodily account in which air modified by sound reaches the ear. Its anatomy belongs to historical medical language rather than an independently verified modern explanation.

Reception of a sound differs from understanding its linguistic meaning, and both differ from accepting a spoken statement as true. Hearing unfamiliar speech illustrates the distinction.

The theological question is who creates the act of cognition, not whether the ear is an ordinarily used bodily means.

16. Hearing Versus Truthful Testimony

Hearing has special importance because much religious learning is transmitted through truthful report, often heard from a speaker. Yet hearing a report is not equivalent to establishing its credibility.

Two speakers may utter competing statements and both may be heard perfectly. Their words reach the ear, but their truthfulness does not thereby become equal. Hearing transmits an utterance; evaluating testimony requires a different epistemic standard.

A written report may be read through sight, but vision by itself does not authenticate its content.

This distinction between the physical channel and the warrant for belief prepares the next discussion of al-khabar al-ṣādiq.

17. The Customary Means and the Creator of Hearing

بِمَعْنَى أَنَّ اللَّهَ تَعَالَى يَخْلُقُ الْإِدْرَاكَ فِي النَّفْسِ عِنْدَ ذَلِكَ
That is, God creates apprehension in the soul at that occurrence.

In the theological account, hearing occurs through divine creation of perception when the ordinary bodily conditions are present. “At the cause” does not grant the physical condition autonomous or necessary efficacy independent of God.

The presence of appropriate physical conditions matters in ordinary hearing. Their role as accustomed means is not denied; the claim concerns the ultimate source of the act of perception.

One must distinguish an account of sensory mechanisms from an account of metaphysical causal efficacy.

18. Two Accounts of Causal Efficacy

The passage contrasts two ways of describing effects: an event occurring at the presence of a cause and an effect occurring through a cause. The former stresses divine creation on the occasion of an accustomed means; the latter may speak of the efficacy of means under divine power.

Classical Sunni theologians discuss these formulations in more than one way. The shared principle is not to grant created things efficacy that is autonomous of God.

The eye and light are ordinary conditions of sight. Whether the result is ascribed to the cause as an instrument or directly to divine creation is a distinct metaphysical question.

The meaning intended by “cause” must be established rather than inferred from the word alone.

19. Sight and the Classical Account of the Eyes

وَالْبَصَرُ وَهِيَ قُوَّةٌ مُودَعَةٌ فِي الْعَصَبَتَيْنِ الْمُجَوَّفَتَيْنِ
Sight is described as a faculty associated with two hollow nerves.

The classical anatomical explanation speaks of nerves connected with the eyes and brain. It should be read as a historical physiological account, not assumed to be a complete modern description of visual anatomy.

The chief epistemic point is that sight apprehends visible qualities such as color, light and shape. The eye is its ordinary bodily instrument.

Seeing the written letters of a sentence and understanding its meaning are distinct processes. Visual presentation supplies information that may require additional interpretation.

20. The Range of Visible Qualities

تُدْرَكُ بِهَا الْأَضْوَاءُ وَالْأَلْوَانُ وَالْأَشْكَالُ وَالْمَقَادِيرُ وَالْحَرَكَاتُ
Sight apprehends lights, colors, shapes, magnitudes and motions.

These name different dimensions of vision: light makes visual presentation possible; color distinguishes appearances; shape concerns outline or surface; magnitude concerns apparent size; motion concerns change in visible position or state.

A rolling red ball may present redness, roundness, apparent size and motion in one observation, though these are conceptually distinguishable qualities.

Seeing a quality remains different from establishing the hidden cause or the complete essence of the object. Visual perception and inference should not be conflated.

21. Smell and the Apprehension of Odors

وَالشَّمُّ وَهِيَ قُوَّةٌ مُودَعَةٌ فِي الزَّائِدَتَيْنِ النَّابِتَتَيْنِ فِي مُقَدَّمِ الدِّمَاغِ
Smell is described through two structures in the front of the brain in the classical anatomical account.

Its special object is odor, pleasant or unpleasant. The passage describes air associated with an odor reaching the organ of smell. This is historical physiological vocabulary, not a complete contemporary anatomical theory.

If a fragrance is perceived in a room while no flower is seen, the odor is sensed directly. Concluding that a flower caused it is an inference that could be wrong; another object may have produced it.

What a sense reports and what we infer from its report must be kept distinct.

22. Taste, the Tongue and the Object of Tasting

وَالذَّوْقُ وَهِيَ قُوَّةٌ مُنْبَثَّةٌ فِي الْعَصَبِ الْمَفْرُوشِ عَلَى جِرْمِ اللِّسَانِ
Taste is described as a faculty spread through nerves associated with the tongue.

Its characteristic objects are flavors. The passage also mentions the admixture of food with saliva, in the framework of a classical physiological account.

Tasting something as sweet or sour does not by itself reveal its entire chemical constitution, medical consequences or legal status. Those require other kinds of evidence and judgment.

A faculty's proper object limits the type of information it directly supplies; taste cannot independently answer every question about what is tasted.

23. Touch and the Perception of Bodily Qualities

وَاللَّمْسُ وَهِيَ قُوَّةٌ مُنْبَثَّةٌ فِي جَمِيعِ الْبَدَنِ
Touch is described as a faculty distributed throughout the body.

The text lists heat, cold, moisture and dryness and related tangible qualities. Contact often yields sensations of warmth, coldness, softness, hardness or roughness.

Feeling a metal surface as cold is a direct tactile experience. Establishing its measured temperature and explaining the physics of heat transfer require further investigation.

The apprehension of a quality must not be equated with full knowledge of its physical cause.

24. Can One Sense Apprehend Another Sense’s Object?

لَا يُدْرَكُ بِهَا مَا يُدْرَكُ بِالْحَاسَّةِ الْأُخْرَى
One sense does not directly perceive what belongs to another sense.

This expresses the specialization of the senses, but a question remains whether the properties associated with one sense may also be known indirectly through another.

A rough surface may look rough, yet recognizing it visually differs from the sensation of touching it. A familiar object may suggest a fragrance by sight, but that is not the same as smelling it.

The claim of specialization is best read as concerning characteristic direct perception, not an absolute ban on every indirect form of recognition.

25. The Conclusion: Senses as Means, Not Autonomous Causes

Three conclusions emerge from the accounts of the external senses. First, each has a characteristic field of perception. Second, further claims about sensed objects may require interpretation, evidence and reason. Third, in this theological framework the senses do not independently create knowledge without divine agency.

Hearing someone's voice is a sensory occurrence; understanding the speech involves comprehension; establishing the claim's truth requires warrants concerning testimony and evidence.

The ordinary value of sensation is therefore not denied, but neither should every impression be treated as an infallible judgment.

The truth of testimony is not settled merely by the audibility of words. The reliability and content of a report require appropriate grounds for belief.