8 Are there other minds, or just zombies?
A definition of 'mind' in linguistic-conceptual-intuitive terms is quite elusive, even if some suggestions may be gained from the common usage of the term. For instance, the expression 'I have a mind', which implicitly introduces a dualism, is much more frequently used than 'I am a mind'. However, premises not fully expressed produce confusion, and guide the investigations along pathways which soon bog down.
Room is consequently available for the conjecture - sometimes declared impossible to be disproved - that all or some other persons do not have a mind. This is in keeping with the fact that certainty about possession of a mind is produced by specific neural centers, whose range of introspective observation is restricted within a single brain.
It may appear convenient to follow, in this case also, a materialistic approach, where a knowable neural definition of mind, in the sense introduced when previous questions were examined, is potentially available. However, this would not assure about the actual, neural existence of the object 'mind', which could reveal itself as an illusory and instrumental concept, devoid of real existence, like celestial spheres and free will.
The advantage of the materialistic approach, however, is that it offers an answer to question n. 8, anyway. Actually, a material mind, if it exists, is expected to be present in every human, given the homogeneity of the biological plan; if it does not, its absence is expected to be common to everyone, including the subject. As to a hypothetical immaterial mind, this, according to the two Postulates, could not act physically nor be physically revealed, and would therefore be irrelevant and undetectable in all cases.
What has been said does not rule out the possibility that zombies be built, emulating human behaviour by architectures and algorithms not implying a mind. Some computer-based systems already appear as attempts in this direction.
It should lastly be noted that the problem whether other individuals altogether exist is a different one, and will be addressed when examining question n. 9.