Any philosophy that claims to be worthy of rational consideration needs to be compatible with evolution.
Both Christianity and Islam have major problems with evolution, and are consequently in headlong retreat into anti-science and irrationalism.
Fortunately, Buddhism has no problem with this aspect of biological science, and indeed rejects the idea of inherently existing species as a form of essentialism.
To Buddhists, species are just separate populations of interbreeding plants and animals. Their defining characteristics have evolved over time and are therefor impermanent. The species do not have any essential nature, nor are they copies of some static Platonic ideal form or divine blueprint in the sky, as drawn up by God during the week of creation.
But although Buddhism is completely compatible with a scientific versus theological view of the origin of the species, it does need to explain 'The Hard Problem' of how non-physical minds have become associated with physical bodies over the course of evolution. Otherwise Buddhism is in danger of losing its spiritual aspects and becoming just another bleak materialistic philosophy.
Automata versus Sentient Beings
One way of approaching the Hard Problem of Consciousness is by asking why humans (and presumably other animals) are sentient, with inner experiences such as pleasure and pain? Why could they not be philosophical zombies - mere automata lacking conscious experience, qualia, or sentience?
In contrast to a philosophical zombie, Buddhism defines a sentient being as one that possesses a mind that can experience qualitative feelings, in particular suffering, unsatisfactoriness or dukkha.
The body of the sentient being may indeed be a physical automaton, but the mind is non-physical. A sentient being experiences its inputs (perceptions) and outputs (actions), in contrast to an automaton where no subjective states occur, and all meanings have to be assigned to inputs and outputs from 'outside the system'.
|The Origin of Suffering according to Christians|
Symbiotic Mind an Evolutionary Perspective
It seems likely that animals above a certain level of development require more than automatic reflexes in order to survive. Advanced organisms need motivation and intention in order to function in complex environments. Motivation and intention are chiefly driven by dukkha - the need to avoid suffering or unsatisfactoriness, and the restless but futile search for lasting happiness. Dukkha and suffering, unpleasant though they may be for the individual, have survival and evolutionary advantages for the species.
To quote Richard Dawkins:
"The total amount of suffering per year in the natural world is beyond all decent contemplation. During the minute that it takes me to compose this sentence, thousands of animals are being eaten alive, many others are running for their lives, whimpering with fear, others are slowly being devoured from within by rasping parasites, thousands of all kinds are dying of starvation, thirst, and disease. It must be so. If there ever is a time of plenty, this very fact will automatically lead to an increase in the population until the natural state of starvation and misery is restored."
Mental states such as suffering, unsatisfactoriness and pleasure are qualia. These subjective experiences, which carry strong immediate meanings, do not exist in automata - mechanistic systems such as relay networks or computers.
It is for this reason that complex animals have evolved neural structures which attract and capture minds. Fundamentally, it is the suffering and grasping of their minds - the need to avoid pain and seek pleasure - that provides the driving force for survival and reproduction of complex animals. The physical body enters into a symbiotic relationship with a non-physical mind.
In Buddhist philosophy, the mind of a sentient being is not a product of biological processes, but something primordial which has existed since beginningless time, and which will be drawn into another body once the present one has died.
Survival advantages of sentience
In evolutionary terms, any adaptation or feature must have some selective benefit for the organism that possesses it. Obviously, a physical body equipped with sentience will have an improved chance of surviving to propagate its genes over any mindless competitor which is not deterred by pain or motivated by pleasure.
But what does the mind gain from this symbiotic association? Usually little or nothing.
When the life of the biological partner comes to an end, it has to endure suffering and then leave its home, being able to take nothing with it. It must then enter the unstable state of the bardo and soon after find a new body. In Buddhist terminology these minds are wanderers or migrators in samsara (the realm of perpetual death and rebirth). The mind is non-evolved and non-evolving (at least not by the normal processes of natural selection).
Parasitic body, parasitized mind?
Perhaps the relationship between mind and body is more one of parasitism than symbiosis. The biological body gets a better chance to propagate itself. But the mind has to endure dukkha - the ever-changing experiences of craving, suffering and attachment that the body imposes upon it in order to force it to do what is necessary for survival, competition and reproduction.
The only way that the mind can escape being endlessly captured and used by biological systems is to permanently escape from the recurrent process of death, attraction to a body, and rebirth. It is this cycle of 'samsara' that Buddhism claims to be able to break.
Participatory Anthropic Principle
Finally, according to one version of quantum theory, the eventual association of physical bodies with non-physical minds was inevitable in order to collapse the superposition of the entire universe.