Chalmers sustains as a main idea that there is not any method that can prove that
scientific theories are true, not even
probably true, as there isn't any method that allows to refute them conclusively. Some of the arguments that support these statements are based in logical and philosophical considerations, and others are based in a detailed analysis of the history of science and the modern
scientific theories. Chalmers highlights two landmarks in the history of the philosophy of science. In the first place Francis Bacon and his intents to show that science try to improve the man's luck picking up facts through the organized observation and deriving theories. In second place, the logical positivism that continues to be a great influence today in spite the questions of Popper and Bachelard. The logical positivism is an extreme form of empiricism according to which the scientific theories are not only justified by the verification appealing to the well-known facts of the observation, but it also considers that they only have meaning as long as they can be derived in that way. In his book, Chalmers intends to show some modern theories on the nature of science and suggest some improvements in them at the end of the book. In the first half of the book he describes two simple but inadequate classic positions: the intuitivism and the falsifiability. Concretely, the chapter 1 describe the intuitivism and in the
chapters 2 and 3 he criticizes it strongly. The chapters 4 and 5 expose the falsifiability as an attempt to improve the intuitivism, but in chapter 6 its limitations are also revealed. The chapter 7 expose the sophisticated falsifiability of Lakatos and in the chapter 8 are introduced the conception of Kuhn and his paradigms. The chapter 9 expose the posture of the relativism, or the idea that the merit of the theories should be judged based in the values of the individuals or groups that contemplate them, and it analyzes in what measure Kuhn adopted this posture and Lakatos avoided it. In chapter 10 Chalmers sketches a posture that he calls objectivism, opposed in some aspects to the relativism. The objectivism deprives the individuals and their judgments of their position of primacy with regard to the analysis of knowledge, and it allows explaining the change of theories in a non relativistic way and in such way that is immune to the critics of certain relativists like Feyerabend. In chapter 11 the author offers his own explanation of the theory change in the physics, and in chapter 12 everything is willing to approach the Feyerabend argument against the scientific method. The chapters 13 and 14, the last ones, Chalmers deals with the question of the realism, according to which the theories try to offer a “real” vision of the world, in contrast with the instrumentalism. In the context of this discussion the author outlines and defends his own posture, the non representative realism. Although this last part seeks to be an improvement of the previous positions, it won't be, Chalmers recognizes it, neither free of problems.