2021-11-28

Book Review: Helmut E. Lück, Kurt Lewin

This is a book that I read spontaneously and only in parts. The book is written in an accessible way; there is no difficulty in skipping sections.

What I took away: Kurt Lewin tries to overcome mechanistic and linear-causal thinking in psychology, using ideas from physics (force field) and mathematics. He starts from a life space, consisting of the person and his environment, which this person passes through and changes in the process. So the person acts and is influenced by the life space, like a compass needle by the magnetic field or an asteroid by the earth's gravitational field.

Lewin has a spatial conception of the life space. As an early example, Lewin describes the experience of a wartime landscape, where he perceived the front as the boundary of the landscape and where the state of war also changes the objects in the landscape, e.g. furniture, and their wartime character becomes visible, e.g. as fire wood or barricades. 

The elements of life space, and this is a central concept of Lewin's, can have (attractive or repulsive) promptive character, i.e. valence (from valency and value). The occurrence of several valences at the same time can lead to conflicts for the person, such as

  - the choice between two elements with positive valence

  - the choice of the lesser evil between two elements with negative valences

  - the approach/avoidance conflict in the case of elements that have both a  positive and a negative valence

The life space as a field with attractive and repulsive forces is one of Lewin's objects of investigation. The readiness to act, the determining tendency of the person is the second field of investigation of Lewin and his students. 

I found the connection to Gestalt psychology interesting. Christian von Ehrenfels generalised the idea of melody into a concept of gestalt, and named oversummativity -- a melody is more than the individual notes -- and transposability as characteristic properties. A drawing of a table is also a gestalt: more than the individual strokes and enlargeable. Lewin now transferred the Gestalt idea to actions and so dealt with unfinished / interrupted actions and substitute actions.

As I said, I have only read a little of the book, and I am leaving some of it out. I didn't find the transfer of topological concepts to psychological phenomena very interesting. 

Since reading it, I walk through my life space with altered attentiveness and notice the valences around me. Trello has it, the sweets on the table have it. The subway coming in makes me stand up, even if it's the wrong line. Thinking in fields reminds me of Porter's 5 forces model and Eckhart Böhme's Wheel of Progress. The idea of actions as movement in the life space reminds me of the customer journey in design thinking.

For that alone, the book is an enrichment.

2021-08-16

Book Review: Keith Richards, PRINCE2 Agile

In March 2021 I passed the exam to become a "PRINCE2 Agile Practioner". The training and the preparation for the exam were very helpful for me to reflect myself as a project manager in a consulting company.

In addition to the training, I had two textbooks at my disposal: the general PRINCE2 textbook ("Managing Successful Projects with PRINCE2") and "PRINCE2 Agile", which I will go into in more detail in a moment. 

First, a brief introduction to PRINCE2. PRINCE2 is (as I understand it) a partially abstract system for describing project structures. I have the idea that some smart people have analysed a large portfolio of projects and have extracted and named recurring structures (principles, themes, processes) from it. For example, I found it interesting that it is not a good idea to bundle certain roles in the project in one person, e.g. project management and project assurance.

While PRINCE2 is quite abstract and formal, PRINCE2 Agile is an adaptation of PRINCE2 that works well for complex projects. Complex projects are projects where it is not clear in detail at the beginning how the project will proceed and are in contrast to complicated or simple projects.

Here, the author brings order to the different agile frameworks. On the one hand, there are agile practices (e.g. Scrum) and tools (Kanban). I use Scrum practices in particular more and more. The "time-boxing" of the sprints reduces stress because it protects against subsequent call-ins. Changes just have to wait until the next sprint. Stand-ups are helpful in a multi-project environment to remind people about the project.

But the word "agile" is not just about a working style. "Agile" needs framework conditions. The client has to be convinced of the iterative way of working and a flexible handling of quality and scope. And the team also needs to get to know agile practices and be willing to try them out. The book highlights this and gives valuable advice on how to achieve each. 

For example, the "Agilometer" is presented, where agility is measured in six dimensions. Because according to the author -- whose name is Keith Richards, by the way -- "agile" is not to be understood categorically (yes/no), but metrically (more or less). In my opinion, the Agilometer is comparable to the newer Agile Fluency Model.

Although I found the book very helpful to learn about agile project management. However, I also needed the impetus provided by the exam, the incorrectly answered questions and the follow-up research. The book is not suitable to browse through in a quiet minute. It is heavily structured, with lots of lists and headings. It is not visually attractive. Therefore, it only gets 4 out of 5 points.

The next step in this topic for me is to apply the methodology to projects of all kinds, to take the time to apply the PRINCE2 terminology to what I am doing. 

2021-07-31

Book Review: Arieh Ben-Naim, Entropy Demystified

 The author explains entropy essentially with a dice-rolling experiment: Given N dice, e.g. all with the six on top, choose any dice (chance no. 1) and roll (chance no. 2). If the experiment is carried out often enough, the sum of the numbers on the dice approaches a value quite stably. It is very likely that the value 6N will not be reached again if N is sufficiently large.

It is clear from the experiment what is meant by (generally not directly measurable) specfic events (the numbers on the individual dice) and by (directly measurable) "dim" events (the sum of the numbers on the dice). I would have been interested to know whether the relationship between specific and measured events must always be linear.

The fact that 6N will most likely not be reached again is an illustration of the "arrow of time".

There are many more specific events that lead to a sum 3N or 4N than to 6N. This seems to me to be the main point of the book.

The author equates "entropy" with search cost, i.e. as a measure of missing information. I would have liked to see a proof of equivalence to the usual definition of entropy (sum of p log p over all p).

These are definitely important insights for me. I'm not sure if I needed to read this at this length to understand it. Why does this need to be discussed for 2, 4, 10, 100 and 10000 dices? And then again imagine that it's not numbers of dice but colours, smells, tastes or sounds?

I don't find the book entertainingly written. The examples from physics (Bose-Einstein configurations, Fermi-Dirac configurations) did not help me as a non-physicist. While reading, I had the idea that one could write a book "Entropy Mystified", where the many applications of this ingenious concept are presented.

2021-07-20

Book Review: David Foster Wallace, Everything and More. A Compact History of Infinity.

 I came across David Foster Wallace through his famous speech "This is Water". I then read some of his essays, about lobsters, about cruises, about severe depression and about how few good books there are on mathematics that can be understood by lay people.

The last essay in particular, "Rhetoric And The Math Melodrama", made me curious about how Wallace himself would write such a book on mathematics. And indeed, Everything and More is a unique non-fiction book.

I like the personal references: Wallace's niece is mentioned, the high school teacher gets a place of honour. I like how Wallace sketches the human side of the mathematicians (Kronecker, Cantor, Weierstrass, Dedekind et al) with one paragraph, I had an immediate image, and contrary to some biographies, I think these images are plausible. 

I also like how he takes elements of textbooks on mathematics and plays with them. Abbreviations suddenly appear that have to be remembered, proofs, "interpolations". It may give a layman a sense of how mathematics is often written then and now.

The many footnotes and "IYI" ("if you're interested") insertions make the revision processes visible to me. Sometimes there is direct reference to notes from the editor, sometimes a footnote nullifies itself, "but in an interesting way". This brings Wallace closer to me, I am not only concerned with the text and its content, but also with Wallace, with the thoughts that (might) have led to the text.

From a mathematical-philosophical point of view, I find §1c particularly interesting, where two types of abstraction are presented: one where the concrete is inferred to the abstract ("horse", "forehead", "horn") and one where different abstractions are linked together ("unicorn"). I also find interesting, even if I don't yet know exactly what I will do with it, the criticism of the "Theory of Types" in §7f, according to which it is be a philosophically bad idea to derive definitions from paradoxes. 

Mathematical induction, the epsilon delta technique and the diagonal proof are presented as techniques for dealing with the infinite. From my point of view, the compactification is missing, although the idea was touched upon. I would also have liked more on the axiom of choice. But I can understand that in a book where Cantor is the focus, it is only mentioned. (For those interested in mathematics: Eric Schechter in Handbook of Analysis and its Foundations really goes into this topic intensively from a practical point of view).

In short: a beautiful book that invites you to pay attention not only to the content but also to the form.

2021-01-05

Book Review: Jesper Juuls, Aus Stiefeltern werden Bonuseltern (German)

This was a gift from my life partner. I like the neologism "bonus parent", but I'd rather be "adult friend" than "bonus dad".

The book is organized by situations or issues that can occur in patchwork families.The book points out possibilities that I would not have thought of myself, and it points out preconceptions or misconceptions that perhaps many people -- including me -- have. 

Still, something makes me not give the book full marks. It leaves me wanting to read more; it remains an introduction.

Another point is that the translator seems to have failed to alternate between genders. (I have read the German edition).