Ibn Sina (980-1037), whose name was Latinized by Christian Europeans as Avicenna, is often called the greatest of the Islamic philosophers, much as Plato is the most popular and extensive in influence of Greek philosophers, Confucius of Chinese philosophers, Buddha of Indian philosophers, and Kant for German philosophers, for supporters and critics alike, such that the course of Islamic philosophy is taught as leading up to and then stemming from the work of Avicenna, by Islamic scholars of the golden age and today in modern scholarship. Islamic logic began in Islamic courts of law from the beginning, but by the year 1000, largely thanks to Farabi and Avicenna, Aristotelian Peripatetic logic was the dominant tradition of using logic to show strengths and faults in arguments. By 1100, Avicenna had taken Aristotle’s place as his superior. While Averroes turned back to Aristotle from Avicenna and Europeans followed him, Islamic philosophy followed Avicenna, and Averroes became more popular in Europe than he ever was in the Islamic world.
Avicenna was born in the village of Afshana in what is today Uzbekistan, his father the governor of a larger, nearby village they didn’t live in, which is an interesting strategy employed today in DC. As a boy Avicenna is said to have learned Indian Arithmetic from an Indian grocer in his neighborhood, read all the Greek philosophy he could find, boiled it down in his notes to the essential points and then rearranged the points into as coherent arguments as he could, producing vast commentaries on many subjects as needed, and he claims to have learned nothing after the age of 18, having read all the texts he could by then, and then maturing year by year as he thought over what he learned.
Avicenna is said to be the foremost doctor of his time, and his Canon of Medicine, translated into Latin like his name, was used as a textbook for Europeans up until the 1700s, as Europe passed the Islamic world in power. His medical practice was based on experimentation and clinical trials, as al-Kindi endorses, fusing Persian, Greek, Indian and other medical traditions together. He hypothesized that diseases are caused by microscopic organisms, randomized control trials, as well as invented terms for hallucinations, insomnia, mania, dementia, epilepsy and syndromes. He was the first to correctly show the workings of the eye, arguing that light does not emanate from the mind and through the eyes in perception, as we do not see in the dark, but rather light goes into the eye from outside, contradicting Aristotle, correctly.
Avicenna was an essential author for understanding Aristotle and scientific investigation, even as he argued against Aristotle on many points. Avicenna claims to use intuition (hads) to judge Aristotle and the Peripatetics, and say whether they should have come to other conclusions or not. Avicenna reinterpreted sections of Aristotle’s Prior Analytics and On Interpretation, two central books of the Organon, and this took the place of Farabi’s faithful Aristotle as the dominant theory of Islamic logic and philosophy, and interest fell away from the others. The Shamsiyya of al Katibi, one of the most popular logic textbooks in human history, focuses on formal questions of Avicenna on these topics.
For Avicenna, intention, or meaning is ma’nan, an idea, the form or essence apprehended by the soul or mind, much as we understand images we see to have meaning beyond the image involved with its form, as well as universal concepts and categories, which mean things, grasping necessity of being or not, beyond the thing perceived. We get the word intention in English from the Latin intentio, which was used to translate ma’nan into the Latin. As the Mad Hatter tells Alice, we really should say what we mean, and mean what we say. This is essence and existence, the mental intent and verbal form, meaning and saying together.
Following Aristotle, Avicenna says there are many ways we grasp things as abstractions, as meanings, such as perception, in which we see color and form with the eye, common sense, imagination, memory, and the highest, intellect. It is not clear if what we call reasoning is common sense, intellect or some combination of these, along with the others, but understanding is grasping things in these ways. The Greek doctor Galen located these in the brain, as did his followers, while others, such as Farabi, located them in the heart, following Aristotle. Avicenna thinks that imagination as highest intellect is always active when we are awake, and our minds wander, or asleep, and our minds dream, but we can direct the wandering mind by placing it under the intellect, which is thinking, which involves the analysis and synthesis, splitting things apart and putting things together, of syllogistic Aristotelian reasoning.
Avicenna argues a sheep can see, smell, hear and, if unlucky, touch a wolf with external senses, which is all fed from the senses into fantasia, common sense. Avicenna says a sheep does not have a human intellect, but does grasp intentions, as in the wolf, what he calls estimation (wahm), what could also be called concern or care, perception of intentions, which are invisible but can be felt, not seen, smelled, heard or touched with the outer senses. The sheep cannot see danger, or the wolf’s wrath, but can put it together with a basic sort of sense which must be internal, something the mind of the sheep adds to the sights and sounds of the wolf. It is not entirely clear in the example if Avicenna means the sheep merely feels the wolf is dangerous, its own fear, or if the sheep feels the wolf’s desire, recognizing it as a creature with motives that are threatening instinctively. Avicenna argues that it is basic to the retentive imagination of the sheep, which we share but also have higher inner senses, and ultimately the imagination and intellect, giving us no clear explanation of where the sheep’s fear comes from, either from instinct or conditioning.
As mentioned with Farabi, Islamic philosophers increasingly turned to the human mind and imagination as the source of reality. Consider that Avicenna, a doctor, was treating patients for hallucinations and dementia while thinking about philosophy and the mind. While Aristotle understood universals, such as the group of all elephants, as a physical set of things, Avicenna argued against Aristotle, by name, that universals are conceptions of the mind, fantasies of sense and imagination. When we speak of elephants, we are talking about our concept, not the set of elephants that currently exist. This is the great debate between essence and existence of Avicenna and Averroes. Does our term elephant refer to what we think, or all actual elephants? Averroes argued that Aristotle is right, and Avicenna is wrong, that the term does not refer to our concept of elephant, but to all physical elephants.
Before Avicenna, the Mutazilites had argued that the most general category of thought is the thing, like Farabi says of being, and things can be further divided into existent and non-existent things. Without a thing, there is no subject for words to communicate anything. In the Quran, it says that God merely has to say to a non-existent thing, BE, and then it is. It is unclear where God finds these non-existents to talk into existence, however, and Mutazilites argued with others about whether non-existents are already in the mind of God or not, much like all possible universes necessarily existing, but in potency, as the infinite imagination of God, which God can make immediately actual.
The Mutazilites, like Avicenna, argued that thoughts, mental categories such as horses, are fictional and non-existent, unlike actual horses and physical objects, so thoughts are, themselves, non-existent, in the same way, they argued, that the concept of unicorns is mental, and non-existent, and so are the unicorns, which also don’t exist, unlike horses but like the idea of them. Our ideas about horses and unicorns are equally real, but imaginary, not physical, and there are physical horses our idea of horses refers to in the world, which is not true of our idea of unicorns, as far as we know from our senses, internal and external.
Avicenna argued that the essence of a thing is its definition, what mental categories can properly describe and contain it, but its existence is its individuality, which is not a mental category. Many who followed Avicenna, such as Suhrawardi (d. 1191) argued essence is primary, superior to objects, while others, such as Mulla Sadra (d. 1640) argued essence is a secondary mental construct. Whether or not they took the side of Avicenna, whatever it may be, most Islamic philosophers, and many Christian Europeans, argued in terms Avicenna framed, even as many, but not all Christian European philosophers preferred traditional Aristotle and Averroes to Avicenna. Sartre, the French founder of Existentialism in the 1940s, argued that existence precedes essence, not the other way around. What he means is very different from Avicenna, that we make meaning, which is secondary to physical, disorganized and illogical existence, actual daily life, deliberately unhinged from the thought of God, taking after Nietzsche.
All of this may seem strange, for a thing to not exist as particularly what it is, but consider that possibilities and potentialities don’t exist, but do, as far as we talk and think about them. Consider someone thinking of opening door one or door two, and can’t do both, so the possibility of opening door A and door B are conflicting and real possibilities, but where are these possibilities? Are they physically real? Are they mental? Some speak as if they are physical realities, like Averroes, but not Avicenna, who like the Mutazilites, treats mental concepts and categories as physically unreal but mentally potent, as capable of producing understanding even if they are not physically existent, like our use of the example of unicorns, which don’t exist, and so serve as a perfectly fine example of an idea that doesn’t “truly” exist.
Whether or not we are determinists, and say there is only one possible future, or open the possibility of free will or chaos, and say there could be multiple possibilities, the possibilities that contradict each other can’t be real and present and remain possibilities. On the one hand, you and I say and agree that there are two possibilities, but on the other we can’t say that something actual is present, because neither door has been opened, and they can’t be equally opened. We share, with others, imaginary space where we imagine possibilities to figure things out, which is what we call part of reality, but it is imaginary and mental, not real. Otherwise, our concepts of horses and unicorns are both equally real, whether or not the idea corresponds to actual things, when in fact both are real as potential, mental things that may or may not go on to correspond to actual objects. Hegel later argued in Germany that possibilities are real, existent examples of types of non-being, which he also understands, like Avicenna, in terms of Platonic and Aristotelian potencies.
Avicenna’s floating man thought experiment should be important and included in any Intro Philosophy class because it is strikingly similar to Descartes’ Deceiving Demon, one of the first major concepts of modern European philosophy. Avicenna, who worked with anesthetics in hospitals such as opium, asks us to imagine that we are slowly unable to feel our feet, then body, then sight and sensation, then memory and imagination. What is left, the last and most essential thing that is ourselves? Avicenna replies that it is consciousness, our awareness of existing even if we cannot think of who or what we are. With that, we still can be said to exist. Without that, it can be said that we are no longer there.
Descartes has us imagine that there is a demon who is deceiving us and creating the world as an illusion, but the one thing the demon can not trick us about is that we are aware. Descartes concludes his argument with the famous declaration, “I think, therefore I am”, though it would be more accurate to say, “I am aware, therefore I am”, the conclusion of Avicenna, as thinking can be removed while awareness remains. Where does the deceiving demon of Descartes come from? The Cathars, Gnostic Manichaean Christians persecuted in France in the 1400s, believed that this world is a lie ruled by Satan, much like the shadows on the wall of Plato’s Cave. The Catholic Church denounced this as heresy, arguing that God rules the world and speaks through the Church. Avicenna uses anesthetics rather than a demon.