In this four page article, Steven Pinker explores what science is and what it is not:
"... science is of a piece with philosophy, reason, and Enlightenment humanism. It is distinguished by an explicit commitment to two ideals, and it is these that scientism seeks to export to the rest of intellectual life. The first is that the world is intelligible. The phenomena we experience may be explained by principles that are more general than the phenomena themselves.
The second ideal is that the acquisition of knowledge is hard. The world does not go out of its way to reveal its workings, and even if it did, our minds are prone to illusions, fallacies, and superstitions.