Wonderful article. The last but one paragraph which states that your teacher is the only person who can imbibe this skill in you and that you cannot acquire this skill at home got me thinking how I acquired this skill to whatever level it is now. At school till the age of 16 it was rote memorisation that was rewarded and didn’t even realise that I could question any of the concepts that were taught. But I was fortunate to join a technical college where my fellow classmates were selected based on tests which possibly included testing ones creativity and critical thinking.. So I grew up with a bunch of bright kids, who were not allowed to voice any difference of opinion in the lecture hall but were totally free to discuss and dissect whatever we learnt in the class room in our dormitories. The college had wisely insisted that all students must compulsorily reside in the campus. The evaluation tests that we had to undergo periodically were designed to test our critical thinking skill in the written format. So I got my critical thinking skills in the oral format from my peers ( to whom I am grateful) and not from any specific teacher that I can remember. From my experience it appears that the environment in which you grow is far more significant/important than any individual teacher/s. That is not to downplay the teacher’s role/ contribution to developing the student’s critical thinking skills. I am just sharing my personal experience.
I liked Tom’s reference to the rest of the iceberg of critical thinking. Many people are confused by creative and critical thinking or see them as being exclusive. I was very pleased to come across a blog entry that understands their interdependence. I think one of the hardest components of critical thinking is the analysis. The part where you are trying to understand what is going on WITHOUT drawing any judgments. If you can do this well, your judgments about what is relevant or accurate or important or whatever will be much more complete.
Searching for evidence of critical thinking in discourse has roots in a definition of critical thinking put forth by Kuhn (1991),  which places more emphasis on the social nature of discussion and knowledge construction. There is limited research on the role of social experience in critical thinking development, but there is some evidence to suggest it is an important factor. For example, research has shown that 3- to 4-year-old children can discern, to some extent, the differential creditability  and expertise  of individuals. Further evidence for the impact of social experience on the development of critical thinking skills comes from work that found that 6- to 7-year-olds from China have similar levels of skepticism to 10- and 11-year-olds in the United States.  If the development of critical thinking skills was solely due to maturation, it is unlikely we would see such dramatic differences across cultures.