it's very easy to define the 'body'. a mere machine for physical actions that requires maintenance to function and subject to growth and decay. i called it a machine because it also serves as an vehicle for the mind and soul's commands and will. however difficulty arises when it comes to defining the mind or soul. it's abstractness makes it slippery to grasp the core understanding of these terms. if you have an idea, an opinion, or just had a sudden revelation, please feel free to post a comment or two.
If you're going to admit that there's a physical body, then further research about it is going reveal the almost all-consuming depth of its processes in producing outward displays of behaviour and consciousness about its environment. The only thing left for 'mind', then, would not be commanding or willing the body to do this or that, but maybe "translating" some of the corresponding neural operations of the brain into various manifestations or phenomenal experiences (visual images, odours, etc.). And that's only an opening if science continues to not care a flip about satisfactorily explaining such, or is unable to do so even it does eventually care.
Although a case against epiphenomenalism or asymmetrical property dualism might be made from the standpoint of asking: How the devil could the brain and its body be addressing the presence of such manifestations in the first place if they have no return effect upon it? Is it simply engaging in fictitious talk or storytelling, and yet by incredibly prolonged coincidence there happen to be experiences actually parallel (in some manner) to the physical processes, so that its stories are accidentally true? ("I see the extended image of a yellow house." . . . "The world is exhibited to me rather than existing in dark and silence.")