Your brain is a mass of cells inside your skull and weighs around 1.4 kilograms, or 3 pounds.
Common sense insists that your mind, with all its amazing powers of thinking and feeling, cannot just
be your brain. The contrary belief that minds are souls is firmly held by the large majority of people
who belong to theistic religions, and by many philosophers since Plato and Descartes. They allow
that the mind may be closely associated with the body and especially with the brain, but insist that
mind and brain are not the same because they have different properties. Your brain has mass, consists
of matter and energy, and ceases to function when you die; whereas your soul weighs nothing, is not
subject to physical laws, and survives your death. Most people today are dualists, believing that a
person consists of both a spiritual mind and a physical body.