Final answer:
A soul is separable from its body if it directly perceives immaterial objects, according to Descartes' view of dualism.
Step-by-step explanation:
A soul is separable from its body if and only if it directly perceives immaterial objects. This is based on Descartes' view of dualism, which posits that the soul is a non-physical substance separate from the body. Descartes believed that the soul exists prior to and independent of the body, and his famous claim, 'I think therefore I am,' suggested that the mind or soul can exist without a physical body. However, it's important to note that modern science has not found any evidence of humans existing without a physical body and brain, and thoughts are now understood to be associated with the brain's physical structure and functioning.