Dualism refers to the view that human beings consist of two distinct substances – material and immaterial. The material substance is the physical body, while the immaterial substance is the soul or mind. This view is contrasted with monism, which holds that human beings are entirely physical.
The philosophical origins of dualism can be traced back to Plato and other ancient Greek philosophers. Plato argued that human beings consist of an immortal soul imprisoned in a physical body. The soul originates from the eternal world of immaterial Forms and becomes trapped in the material world. At death, the immortal soul is freed from the body to return to the realm of Forms.
In the 17th century, the French philosopher René Descartes formulated the most famous version of substance dualism. Descartes started from a position of radical doubt, asking what could be known for certain. He concluded that he could not doubt his own existence because the very act of thinking necessitated that there be a thinking thing (cogito ergo sum). From this starting point, Descartes reasoned that there must be two kinds of substances – material and immaterial. The material substance is the body, which Descartes viewed as functioning mechanistically as a machine. The immaterial substance is the mind or soul, which is conscious and possesses capacities for thought, judgment, and volition.
For Descartes, human beings therefore consist of two separate substances that interact. The body is extended in space, subject to mechanical laws, and divisible. The mind is unextended, not subject to mechanical laws, and indivisible. At death, the two substances are separable – the body disintegrates but the immaterial mind or soul persists. Descartes located this interaction between body and mind/soul in the pineal gland of the brain.
There are several major philosophical issues raised by substance dualism. First, there is the question of how two radically different substances such as mind and body can interact at all. This is known as the “mind-body problem.” There is also the question of whether substance dualism inevitably leads to epiphenomenalism – the view that the mind is a mere byproduct of physical processes without any causal powers. Relatedly, critics argue that substance dualism is inconsistent with naturalism and a scientific worldview, since science seeks to explain phenomena in terms of physical causes.
In terms of the Bible and Christian theology, dualism has been highly influential. Many biblical passages suggest a dualistic view of human nature, such as Matthew 10:28: “Do not fear those who kill the body but cannot kill the soul.” Human beings seem to be composites of physical bodies animated by immaterial spirits or souls. The doctrine of the resurrection of the dead also implies a form of dualism, as it holds that the material body dies but will be raised again.
There is debate among Christian thinkers as to just how dualistic a view the Bible presents. Some argue that Hebrew thought had a more holistic conception of human nature. However, many influential theologians such as Augustine have embraced forms of substance dualism. The doctrines of the image of God and the fall into sin also seem to imply an immaterial component that distinguishes humans from animals.
Dualism has been a crucial concept in philosophical and theological anthropology through the centuries. While monistic views challenge dualism today, the consensus historically in Christian thought has been that human beings consist of two fundamental substances – body and soul/spirit. The exact nature of this relationship continues to be debated among philosophers and theologians.
Here are some key Bible passages related to dualism and the human constitution:
Genesis 2:7 – “Then the Lord God formed the man of dust from the ground and breathed into his nostrils the breath of life, and the man became a living creature.”
Ecclesiastes 12:7 – “And the dust returns to the earth as it was, and the spirit returns to God who gave it.”
Matthew 10:28 – “And do not fear those who kill the body but cannot kill the soul. Rather fear him who can destroy both soul and body in hell.”
1 Corinthians 6:20 – “For you were bought with a price. So glorify God in your body.”
James 2:26 – “For as the body apart from the spirit is dead, so also faith apart from works is dead.”
The key aspects of a dualistic view highlighted in these passages are:
- Human beings have both material and immaterial components
- The body is not the whole person – there is a distinction between body and soul/spirit
- The soul/spirit persists after bodily death
- There is an integral, interactive relationship between body and spirit
The Bible does not contain one definitive doctrine of human nature. But substance dualism has been the predominant model throughout most of Christian history. This view aligns with some of the intuited differences between humans and animals, such as consciousness, reason, morality, and the longing for eternal life. It offers an explanation for how personhood continues between bodily death and resurrection.
Of course, substance dualism raises many philosophical issues. Some of these include:
- How can two radically different substances interact causally?
- Is the soul contained wholly within the body or can it exist independently?
- What is the relationship between personal identity and the soul?
- How are unity and interdependence between body and soul maintained?
- What are the implications for understanding human freedom?
These are complex debates that continue up to the present day. Dualism has its critics as well as proponents. But it cannot be denied that dualism, in some form, has been prevalent in Christian thought about human nature. Resolving the philosophical difficulties satisfactorily remains an ongoing project.
In summary, dualism holds that human beings consist of two fundamental substances – a material body and an immaterial mind/soul. This view has biblical roots and can claim substantial support throughout Christian tradition. However, various philosophical problems with dualism remain unresolved. The exact nature of the relationship between the physical and spiritual components of humans continues to be explored and debated.
Substance dualism has been highly influential in western philosophy and Christian theology. But there are other positions on the nature of human persons proposed as well:
- Monism – The view that human beings are entirely physical. The mind is just the functioning of the brain rather than a separate substance.
- Hylomorphism – The view that humans are a composite of matter (hyle) and form (morphe). Matter and form are not distinct substances but metaphysical components.
- Emergent Dualism – The view that mind emerges from and is dependent on the brain but is still irreducible to it.
- Eliminative Materialism – The view that talk of the mental will eventually be eliminated in favor of purely material explanations.
Each of these views has its defenders and critics. Resolving the fundamental nature of human persons remains a complex challenge. But dualism, in asserting the distinct reality of physical and mental phenomena, aligns with deep intuitions about selfhood and the contours of human experience. This may account for its persistence despite philosophical difficulties.
The debate around dualism also intersects with a number of other important theological issues:
- The image of God – Is the image of God in humans restricted to the spiritual component or does it encompass both body and soul/spirit?
- The fall – Did the fall affect primarily the spiritual component of humans or human nature more holistically?
- Salvation – Does salvation focus just on the soul or the whole person?
- Resurrection – Will the resurrected body be identical to or transformed from our earthly bodies?
- Ethics – Does our physical embodiment shape our moral decision making?
Dualistic assumptions can influence perspectives on these issues. For example, a stronger dualism may imply that the image of God is restricted to the spiritual component. Or that sin has corrupted only our spiritual faculties while physical processes remain neutral. On the other hand, non-dualistic views will emphasize the integration of the physical and spiritual in theological anthropology.
In conclusion, while variants of dualism have been prevalent in Christian thought, the debate continues today. There are thoughtful Christian perspectives that challenge substance dualism. There are also various mediating models that attempt to thread the needle between monism and classical dualism. However we conceive human nature, a robust theological anthropology will grapple seriously with what it means to be created as ensouled bodies in the image of God.