Richard Swinburne

A substantial balance of evidence favours the view that human souls have libertarian free will, that is the freedom to choose between alternative actions, despite all causal influences acting on them. Free will thus entails soul indeterminism, which entails brain indeterminism. There is no reason to suppose that the same laws govern the behaviour of the brain as govern any other physical system, since the brain is different from any other physical system in being in causal interaction with a soul. In any case, its indeterminism may be ensured by Quantum indeterminism. The main evidence for soul indeterminism is, however, the fact that human counter‐suggestibility would be compatible with determinism only on the assumption of an a priori very unlikely mechanism for the production of beliefs. New Appendices E, F, and G discuss the relevance to this topic of different interpretations of Quantum Theory, of Gödel's Theorem and of Libet's experiments.

We have no grounds for supposing that a foetus has a soul until it is conscious, and no grounds for supposing that it is conscious until there occur in it brain processes similar to those that accompany consciousness in more developed human brains. The higher animals have souls. While scientists may discover vast numbers of correlations between mental events and brain events, it is most improbable that they will be able to explain why there are the correlations that they are, or any correlations at all – that is, why neural systems of a certain complexity give rise to souls. The very success of science in achieving vast integrations of theories in physics and chemistry was achieved by separating off from the physical world colours, tastes etc; but this cannot be done when we are looking for a theory with psychophysical laws.

The Council of Chalcedon declared that one individual, Jesus Christ, had two natures – divine and human. His divine nature must be regarded as consisting of the essential divine properties plus the specific properties essential to the second member of the Trinity. The human nature must be regarded not as a substance, but as the contingent properties analysed in Ch. 1 that make someone human. New Testament and later‐Christian doctrine require that we understand the two collections of properties as instantiated somewhat separately from each other, so that Christ has two minds, a divine one and a human one, the human one not being fully aware of the divine one. Although Christ could have done no wrong, he could – but did not – yield to temptation to do less than the best.

Evidence of ‘near‐death’ experiences, parapsychology, and claims of reincarnation do not constitute very good evidence that human souls survive the death of their bodies. Nor are there good philosophical arguments for the natural immortality of souls. Yet there are no natural laws connecting the existence or functioning of a soul with the existence or functioning of a body. Only an argument via some very general metaphysical theory could show what happens to a soul after death – e.g. an argument to a God who has revealed what happens.

God does not need to become incarnate, i.e. human, to forgive us, but it is good that he should do so to make his forgiveness available to us by means of an atonement for our sins; and also for many other reasons – to identify with our sufferings, show us how much he loves us, and reveal truths to us. Evidence that Jesus was God Incarnate is provided by the kind of life he led, and its culmination in the Resurrection. Other accounts of the ‘incarnation’ – monophysitism, Nestorianism, the Kenotic Theory, and modern humanistic Christologies – are less probable than the Chalcedonian one. The chapter concludes with a brief discussion of the Virgin Birth, and the Ascension of Christ.

A substance is a concrete individual thing that exists all at once. Although the world can be cut up into substances in different ways, any full description of the world will include both material objects and immaterial souls as substances. Souls have essentially mental properties, ones to which the subject has privileged access such as thoughts and sensations. The essential part of a human being is a human soul, one with a structure and a capacity for logical thought, moral belief, and free will, and certain limited powers exercised through a human body. No human being is essentially human.

Sentences can be thought of as expressing propositions or statements. The logical nominalist is right, against the logical Platonist, to hold that propositions and statements are not really existing things but mere useful fictions. A sentence is logically necessary if its negation entails a contradiction, given that its referring expressions in fact pick out the objects that they do. A sentence's entailments are a matter of the human conventions for the use of that sentence. There are kinds of necessity other than logical necessity. In particular, there is what I call ‘ontological necessity’ – everlasting uncaused existence; and what I call ‘metaphysical necessary’. Something is metaphysically necessary in my sense if either it is ontologically necessary or it is inevitably caused to exist everlastingly by something ontologically necessary.

Desires are natural inclinations, hard to change, to do certain actions or allow certain events to occur. Enjoyment consists in the believed satisfaction of present desire. We always act on our strongest desires, unless we have good reason for not doing so and then we have to choose between reason and desire. Weakness of will consists in yielding to desire when reason suggests that we should not do so. Modification of desire is distinguished from forming an intention for the future, which in turn is distinguished from having an intention in one's present actions.

Personal identity cannot be analysed either in terms of a continuity of mental life, or in terms of continuity of bodily matter. Continuing personal identity in the short term is a datum of experience, not merely known by inference from other experiences. To express this fact within an integrated system of thought, we must think of human persons as substances that consist of two parts – soul and body. Part 2 of this book develops this view more fully. The argument of this chapter is put in precise logical form in New Appendix C. New Appendix D claims that souls have thisness; that is, the indiscernibility of identicals does not apply to souls.