Often, a good way to begin the process of thinking critically
about a subject is to do some conscious thinking about it before you
do any reading or hear any presentations in the subject. Thus, if you
are going to study biology or sociology or writing, a good way to
begin is by writing down some of the main ideas you already have
about biology or sociology or writing itself before you do any reading
or listen to lectures. This allows you to be an active listener rather
than a passive recipient of information. It helps you to become aware
of your assumptions about the subject so that you can assess them
more accurately in light of what you will later read and hear.