Thomas Aquinas: Philosophy of Knowledge, Humanity, and Society
Knowledge
The knowledge of Thomistic theory is built on its substantial human conception. Faced with Augustine of Hippo, who believes that he knows the soul using the body as a tool for knowledge, Thomas Aquinas (TA) offers a measure of the substance that is man: the composite of body and soul. Therefore, following Aristotle, TA considered that knowledge begins with the information the senses provide us with, the feeling, which is always concrete and particular. He claimed there is nothing in the understanding that has not previously been in the senses. From the data supplied by the senses, the intellect abstracts the essence of each object because the object of the intellect is being, the essence of things, the universal.
Thus, the understanding has two activities: firstly, to abstract the essentials from the perceived, and secondly, to formulate an abstract, universal concept, fundamental to science. The process of understanding is developed as follows: First, the senses capture the particularly sensitive subject. The sensory image of that object that has been captured by the senses, or ghost, is recorded in the imagination or fantasy, leading to sensitive species expressed. From here, the agent or active intellect abstracts the essential image, printing the intelligible species, which is an intangible representation. Then, the “possible or liability” expressed produces the intelligible species, that is, the concept, which is always universal and abstract. Understanding is passive because it is in power until it receives the intelligible species printed, and developing the concept begins.
TA believes the intellect knows the universal directly, while concrete beings are known indirectly. For example, when we see a particular man, Socrates, say, the understanding, once it has the universal concept of “man,” applies it to the particular object image and makes the trial “Socrates is a man.”
The Nature of Man
The conception of human beings in TA’s philosophy is articulated through the hylomorphic theory of Aristotle: Man is a substance composed of matter and form. The form is the rational soul which reports directly to the subject, so that man is a unity, not the body alone, nor the soul alone, but the substance composed. The unique human soul gives all determinations: its corporeality (as the soul informs the field) and vegetative functions, sensitive and intellective. At death, the body ceases to be informed by the soul and corrupts. Operations fail to act rational, sensitive, and vegetative. Instead of human substance, we have a multiplicity of material substances.
Both soul and body belong to the heart of man. This is a fundamental difference with respect to Aristotle’s view because the essence for him was the way, not including the matter. According to TA, the same reasoning is that feeling grows, and so on. The union of soul and body is natural, not accidental as it was in Plato. The human soul can have the feeling, but it needs the body. It has the power of insight, but it has to form its ideas from sense experience, for which it needs the body. The union of soul and the human body is not a punishment, as Plato said, because the body exists for the form, not against the form.
Against Aristotle, TA asserts the immortality of the human soul. Despite the substantial union of body and soul, the human soul is immortal because it is a subsistent form; it does not need the body to exist. (Unlike the human soul, the soul of animals is not a subsistent form; it depends on the body for all operations, both the vegetative and the sensitive. Therefore, it is corrupted when the body decays). That the human soul is essential is demonstrated by the fact that it can meet all natures. Material would be determined if a specific object, like the eye, for example, can only see light or the ear can only hear sounds. But the human soul can know all material things or not, including the nature of men and herself. Thus, what we need is spiritual and therefore incorruptible.
Ethics and the Pursuit of Happiness
Moreover, the soul has a persistent desire, a natural desire for immortality; of man is knowledge. And a natural desire, as such, implanted by God, cannot be in vain. From here arises the effect of ethical theory. Like Aristotle, TA believes that human beings tend to an end, the highest good. For Aristotle, it was contemplation, which was achievable in this life. But for TA, the supreme good is transcendent; it is God. For the sake of God is dependent on everything else, and things are, therefore, ordered. Thus, unlike Aristotle, TA believes that the ultimate good, happiness towards which human beings strive, cannot be achieved in this life, for being the supreme good is perfect happiness, which includes the beatific vision of God. This happiness is an act of understanding, not natural knowledge. It’s a seeing God and knowing Him as He is, a gift from God.
Society and the Role of Law
Unlike Augustine, who believed that the state and its laws were a historical necessity as a result of original sin, TA, like Aristotle, considered they are a natural need. However, the ethics and politics of Aquinas are also complemented theologically. TA believes that the rules to be followed by humans are still in their very nature. Indeed, like all of nature, man has a natural tendency but, unlike the rest of us, he can know them by virtue of their rationality and extract those rules of conduct, either by deduction or by specifying more general rules.
Thus we have:
- The tendency to preserve their own existence must be a moral duty to preserve life.
- The tendency to procreate derives the duty of caring for the couple and their children and educating them.
- The tendency to know the truth and live in society comes the moral obligation to seek the truth and respect justice.
These precepts are the natural law, which is only part of the Eternal Law by which God governs the world with providence. The Eternal Law is rooted in the nature of all beings and tends to his Creator. Unintelligent beings are governed by the laws of physics and intelligent beings, by moral law, whose first precept is to do good and not evil. Therefore the moral law is the eternal law concerning human behavior. And human behavior is guided by conscience, which would be the measure by which we apply the principles of natural law to our actions, and by virtue, as Aristotle said, is a stable disposition to do good.
Characteristics of Natural Law
The characteristics of the natural law are:
- Universal because human nature is common to all human beings.
- Evident because its precepts, to be grounded in human nature, are easily knowable by all humans.
- Immutable because human nature remains unchanged, is always the same despite changes in society.
Natural law must be respected by positive law. Positive law (the laws governing human societies) is imperfect. It must respect the natural law to be fair; otherwise, it would be a corruption of the law, says TA, as Augustine said. And it also has to realize that, because natural law is very general. Positive law does not repress all vices but only those that harm others, nor prescribe acts of virtue, but which are necessary to preserve the common good.
The State and its Relation to the Church
Like Aristotle, TA believes that society is natural and that the state must work for individuals to achieve their right. Along these lines, consider the government as natural: as the head must rule the body, the government has to govern society. Indeed, the state needs a government that unifies the company and guides the activities of citizens to the common good. Within the individual, the State has power but, as we saw, the supreme good toward which the human being is God. Since the Church is the institution that leads the faithful to God, the supreme good, the State will be subject to the Church. Well, the government and the state are loved by God, who rules the world through Eternal Law. God comes, therefore, the moral law that positive law must comply, as power.
Unlike Augustine, who believed that the state and government were the result of original sin, TA considered that they are loved by God. As with the relationship between faith and reason, true church-state relations: each has its own area but the state must be subordinated to the Church because the ultimate goal of this is the ultimate goal of the human being: God.