A point repeatedly emphasized in this course is the distinction between the purely mental activity thinking and the intentional outcome of critical thinking . Mental activity may include our daydreams, fantasies, hopes, desires, or wishes. Yet when the impulses arrive at an instrument ready to act upon the them, they are transformed into action whose effects can be measured.
Mental activity reveals no meaningful, measurable effects on the objective world.
Indeed, an EEG scan can determine whether or not the brain is alive and functioning, but toward what end is a mystery. Critical thinking is the leap into the meaningful, volitional, objective world. But first, you may need to consider the metaphor of the brain as an electronic transceiver. As such it receives and transmits electrical impulses. It receives data from the external world and interprets it.