Paul Meehl asks himself the question what "how can we predict how a person is going to behave?". He distinguishes 2 main approaches: clinical interviews VS statistics (psychometric tests) and discusses the pros and cons of both approaches.

For decades psychologists have been struggling between the use of tests (statistics) and (clinical) interviews. I ran into the problem myself when I did a Whiplash study in 1999 and found that many doctors made clear mistakes during the patient's LAB Profile interviews, to such an extend that the produced data was unreliable for further research! Since then, I reluctantly moved over to the testing side and co-developed the iWAM test (see jobEQ.com), but I recommend complementing tests with structured follow up interviews to check the validity of the test answers.

One of his main points pro testing is that "Every hour a clinician spends in thinking and talking about whom to treat, and how and how long, is being subtracted from the available pool of therapeutic time itself." The main counter argument of a clinician will be that every individual is a separate case and thus becomes hard to find in the numbers.

In global, one can say that Meehl holds a quite impartial point of view and tries to present approaches in a factual manner, trying to bring them together. A slight bias towards testing may be expected, given that Paul Meehl was a professor of Psychology and psychiatry at the University of Minnesota and also wrote a book on the clinical use of MMPI.

Complementary books you may what to read are "Psychological testing" by Kaplan & Saccuzzo (2001) and "How to think straight about psychology" by Stanovich, 2001

This is that while the announced intention of Cold War data systems efforts was to indeed provide a logically closed structure that would ensure national security and a narrow form of economic growth (which excluded unions from power), as Edwards himself reveals, these systems in significant ways failed to accomplish their technical goals.

The problem is that people with the traditional liberal suspicion of computers miss either this fact or fail to grasp its significance. Edwards fails to grasp its significance.

What it means is that on the ground, in the apparently highly controlled mainframe computer rooms, a highly "open" and possibly even "green" for of chaos operated as software (in one noted example) bayed at the moon when it mistook the moon for a missile. This chaos was presented as its opposite in a rhetorical trick which conceals the labor, and in some cases the very existence, of software creation.

The troubling fact, invisible to humanists outside the field, is that the upper-level administrators of these systems did not really care that they did not work, as long as the public viewed them as a closed and working system. They'd also prefer to conceal the origins of the software that controls these systems in labor and in writing.

Edwards in the main fails to link this rhetorical sleight-of-hand to C. Wright Mills' work in which the general public is systematically deceived, and a white-collar class creates the tools of its own destruction.

The Sage air defense system did not work and did not, in fact, protect the United States from attack: what protected us from attack was the decision of men to back down from macho and nuclear-armed confrontation, including Eisenhower's decision to not back Britain, France and Israel in 1956's Suez crisis and Nikita Krushchev's decision to back down in 1962 over Cuba.

The real technical illusion is not that the closed world is "better than" the green world. It is to not fully close digital worlds but to present them as closed, and to prevent the rules of their closure from public oversight, and control.

The author has come a long way since the first book in this series which I thought was forced and formulaic. This book is informative and a tight, well-written mystery and well worth reading.