Chapter 3: Tools of Knowledge 1

And among His Signs is the creation of the heavens and the earth, and the difference of your languages and colours. Verily, in that are indeed Signs for men of Sound knowledge. The Holy Qur'an [30:22]

Knowing that we really do exist and there is an existing world around us, the next question arises as to what the reality of knowledge is and how can we gain knowledge about ourselves and the world around us? What types of Tools of Knowledge do we have? What is the relation between the knower and the object known? How much of the real world is accessible to us?

Types of Knowledge

Human knowledge is divided solely into two types:

  1. Knowledge by presence. Like the knowledge everyone has about one's self. Such as the knowledge you yourself have about your feelings. In this type of knowledge the knower and the known object are unified.

  2. Acquired knowledge. This is most types of human knowledge and is also the one that we will mainly deal with in this chapter.

Definition of Knowledge

Imagine a picture of a natural scene is shown to you. The size of the picture is 10 X 15 cm. In the picture you see a landscape that you know is about 5 square kilometers surrounded by tall mountains.

A river which you approximate it's width to be fifty meters is crossing the middle of the view. At the river's bank from both sides you can see tall white silver firs lined up. Your family is also seated under the trees having their lunch. I could go on more, describing further details of the picture.

Now, if your friend were to ask you if the picture you have at hand contains all the length, width, depth and physical characteristics of that landscape, how would you reply?

“Obviously not”, you will reply without hesitation. All that would not fit in such a small space. What are really on the paper are some colourful spots. Yet, it is the image of the landscape.

The function of our mind is similar to a camera, or a mirror, which reflects the image of the object known.

Although knowledge does not really need any definition, it is sometimes defined as:

The presence of the image of an object in mind.” [al-modhaffar: Al-manteq] Therefore, knowledge is the bridge of converting a real external object, in its true form, to its reflection in one's mind.

Differences between Mind and Mirror

Despite similarities between the function of the mind and that of the mirror, there are at least five differences, which uniquely characterise the function of mind.

  1. Reflection of meaning: A Mirror reflects solely optical images. In other words, if a man is standing in front of the mirror, it will show his body shape, colour and size. The mirror under no circumstances reflects his knowledge, feelings, hatred or love for others etc. However, the mind can reflect not only the sensible objects but emotion and feelings as well.

  2. Non-correction power: If the mirror is concave it shows the object bigger than its real size, and smaller if it is convex. It has no power of knowing its mistakes or any ability to correct them. However, the human mind can uncover the mistakes of illusions and is also able to correct them explaining why and how the illusions and delusions occur.

  3. Self-reflecting: no mirror in the world can reflect its own image to itself, whereas the mind is capable of reflecting others images as well as its own. Rather the mind's own reflection is far more accurate, a phenomenon called ‘knowledge by presence'.

  4. Generalization: A mirror will only reflect objects put in front of it. It has no power of reflecting any other object around it. However, the human mind recognizes and reflects sighted objects as well as being capable of linking them to numerous similar objects and applying the same rules to them. Scientific laws are derived from the means of this characteristic of the mind.

  5. Deepening: Any mirror will only reflect the object in front of it. It cannot convert the reflected object to another mirror to reflect another object. By contrast, our mind is able to change an object known to another reflective object reflecting the reality of a third known object. This is called a ‘ Sign Knowledge ', which will be explained later in this chapter.

Ignorance and its types

Before we proceed any further to discover the sources of human knowledge, let me share with you the meaning of ignorance and two types of it.

Ignorance by definition is lack of knowledge on the part of one who is able to obtain knowledge.' Thus, a piece of wood or a rock, are not ignorant as they are not capable of obtaining knowledge.

Ignorance is also divided into two types:

  1. Simple Ignorance: This means a type of ignorance where the person is aware of his ignorance. The famous saying of Socrates “Wisest is he who knows what he does not know” refers to this first type of ignorance.

  2. Compound Ignorance: Is a type of ignorance where the ignorant is unaware of his ignorance and moreover assumes that he does know. Compound ignorance is the combination of two types of ignorance; firstly ignorance about the truth and secondly, ignorance of the fact that he does not know the truth. The example of compound ignorance is optical illusions such as mirage.

Tools for Acquiring Knowledge

Sense experience

Nature is the first human source of knowledge and our five external senses are the tools of accessing this source.

From the time we are born, we hear sounds around us, we see objects and people around us, we touch and taste and smell things and through each we gain some knowledge accordingly.

Human beings are similar to animals at this level, with the only difference being in the level of perception between humans and some animals. For instance, the sense of smell in dogs and ants is stronger than in humans, as are the navigational skills of a bat stronger than a human. Dogs see are only able to see the colour gray etc.

In spite of the differences in depth of sensory perception between humans and animals, it is common-sensical that for a healthy human being, external senses are the first tools of obtaining knowledge to the extend that it is said in Arabic: “One who misses a sense misses a knowledge”.

However, there are different opinions among philosophers from ancient times to the present about the validity of our sense of perception. Plato, for instance, did not accept nature as a source of knowledge; his reason being the relationship between mankind and nature is interlinked and therefore cannot bring about knowledge.

Descartes and Kant also hold the view that sensory perception is good for daily life experiences yet it is not a reliable tool for obtaining knowledge. 1

In contrast, empiricists assert that human knowledge arises from what is provided to the mind by the senses or by introspective awareness through experience. John Locke, the English philosopher of the 18th and 19th century, was the first to give this systematic expression to empiricism followed by George Berkeley and David Hume.

According to empiricism sensory and sensational experience are the only tools to feed the human mind with knowledge. Thus, we can only understand what we can physically perceive. Even when one imagines a mountain of gold, is it because you have already seen a mountain of gold? Or rather because you have seen a mountain and you have seen gold? Your mind then combines these two sensational perceptions into one.

Positivists, such as French mathematician and philosopher Auguste Comte of the 19th century, further developed the idea of empiricists and based their philosophy on experience and empirical knowledge of natural phenomena, in which metaphysics and theology are regarded as inadequate and imperfect systems of knowledge.

During the early 20th century a group of philosophers who were concerned with developments in modern science, rejected the traditional positivist ideas that held personal experience to be the basis of true knowledge and emphasized the importance of scientific verification. In short, the main theory of empiricists is that without sensory perception, we have no knowledge about the world.

Characteristics of Sensory Perception

a. Individualist: The first characteristic of sensory perception is that it is obtained individually. For instance, a child gradually gets to know her mother, then father then brothers and sisters and so on. She has no idea of human kind in general.

b. Appearance: Sensory perception also shares with us the appearance of the objects. For instance, your eyes can only bring knowledge about colours and shape and size of an object. It cannot show us the depth and the nature of it.

c. The Present: Sensory perception belongs only to the present time. It cannot show us the past or the future. In other words, you cannot observe the events prior to your birth. (remember the film of past events is not the event itself.)

d. Regional: Sensory perception is also limited by place. Human and animals can obtain sensational knowledge of the area, which is within their vision or hearing. For instance, as far as sensory perception is concerned, we have no sensational knowledge about the surface of the moon, for in order to do so, one would have to have had personal sensational experience of it.

Comments on Empiricism

Although it is agreed that sensory experience is the first and foremost elementary tool of knowledge for humans and animals, we do not limit the tools for which to gain knowledge, to the senses for the following reasons:

1) Senses can only show us objects. The relationship between them is uncovered by the means of rational thinking. For instance, our eyes can see the key and the lock, but the functioning relationship between them is known by the rational law of cause and effect. In other words, no scientific law could be possibly obtained without rational analysis attached to the sensory experience.

Unfortunately some of the empiricists such as Hume have denied the law of cause and effect, as it would not be compatible with the theory of empiricism. He explained that the relation between the unlocking by means of a key exists by what he calls ‘mere association' which makes us believe the relation is permanent.

His point is that all human knowledge is based on the theory that ‘if A therefore B' and includes his hypothesis ‘or else'. He cannot, however, suggest a certain idea either. (Pay attention!)

It is important however to note that in addition to linking objects by cause and effect, so many objects of natural phenomena come into association with each other such as day and night, pen and pencil, book and library, yet we never relate them to each other as cause and effect.

2) Sensory experience cannot denote the impossibility of the impossible. For example, sensory experience cannot denote the existence of a triangle with four angles, simply because the senses have no ability to experience such things.

3) Mathematics is the most certain science yet it is not experimental. In fact, many of its concepts cannot be experienced by the senses. For example, there is no circle in the real world where the distance between its perimeter and the centre is exactly the same from any point.

Rational perception

In light of the above explanation, it is obvious that reasoning and rational analysis are the second necessary tools for obtaining knowledge in humans. In addition to this, there are certain types of mathematical knowledge such as geometry, which is considered the ideal for all sciences and philosophy.

However it is important to note that there are certain geometrical rules that are universally agreed upon as to their certainty by the means of reasoning alone.

This fact has obligated some philosophers such as Rene Descartes and Immanuel Kant, to form the doctrine of Rationalism, which emphasises the unique role of reasoning in obtaining knowledge, in contrast to empiricism, which emphasises the role of sensory perception to obtain knowledge.

We believe reasoning is the higher tool of obtaining knowledge and is the very tool, which distinguishes the realm of humans from the kingdom of animals.

Nonetheless, we do not agree that reasoning is the sole tool of obtaining knowledge. In fact, the main problem of empiricists as well as rationalists is that each one tries to generalize a tool beyond its own world.

Empiricists are correct in a sense that most natural knowledge cannot be obtained without enjoying sensory experience, just as it is impossible to explain to a born blind the difference between the different colours. Thus, it amazes us to learn that Beethoven, one of the greatest musicians of all time, had lost the sense that he would have relied on most, his sense of hearing. However, he was not born deaf.


One of the greatest tools of obtaining knowledge is what is introduced to mankind by the Holy Quran, named ‘ the tool of Sign'.

The contemporary Iranian Muslim philosopher; Motahari is perhaps the first who discovered this as a tool of human knowledge. Most human knowledge is in fact obtained by the means of signs. According to Motahari and other Muslim philosophers “epistemologically there is no difference between knowing about Napoleon Bonaparte and knowing God in a sense that we people of the 21st century have not eye witnessed any of them.

Therefore, since we know about Napoleon by means of some historical signs affirming his existence and life, similarly we know about the existence of God by the means of natural, rational and other types of signs glorifying His existence. The Holy Qur'an considers the entire world “Divine Signs”. For instance, consider the Ayat of 20-22 in chapter 30 of the Holy Qur'an:

And of His signs is that He created you from dust, then lo! Ye are human beings scattering (in the world). And of his signs is that he created for you from your selves, mates that ye may dwell (inclined) unto them, and caused between you love and compassion: Verily in this are signs for a people who reflect. And of His signs is the creation of the heavens and the earth and the variety of your languages and your complexions; verily in this are signs for the learned (ones).”

When your teacher gives you a lesson, how would you know about his knowledge level? Is it that his eyes, face, height, or any other part of his appearance reflect his knowledge, or is it that the subject he is sharing with you is like a sign (secondary mirror as explained in the beginning of this chapter) reflecting his knowledge to you?

When you really pay more careful attention to most human knowledge, you will agree that most of our knowledge is in fact obtained in such a manner. Therefore, the one who is limits his knowledge to whatever he can experience by his surgical knife instead of the library has already closed his eyes to most human knowledge.

asked about his library by one of his friends he took him to his backyard showing him the dissection of a calf as being his library.

  1. This, incidentally is in spite of the fact that when Descartes was