# Summer 2021 reading notes

Here are my summaries and reflections of some of the books I read during summer.

## Information: A Very Short Introduction, Floridi 2010

This book was recommended to me alongside other Luciano Floridi’s books namely The Philosophy of Information and The Logic of Information. For quite a long time I’ve been interested in Floridi’s idea that by and through understanding the concept of information, we may better understand the world since we understand any concept through information in the first place. In the book, the concept of Information is examined from various and continuous perspectives. The book is indeed very introductory, yet it builds the most necessary understanding. It leads us all the way to the ethics of information at the very end, which is perhaps the most fruitful part. Even though it's an introductory text, this chapter required more thinking and a change of perspective for me.

It is the idea that ”the space we inhabit is not just the earth” is the basis of information ethics. Information ethics is viewed from the ontological perspective. All entities, living and non-living, including digital, are informational objects and they are not only viewed as interacting with an outer environment. They are viewed as being surrounded by and being part of the infosphere. Each entity’s influence and commitment to the infosphere is crucial because the preservation and flourishing of the entities against entropy is the purpose. The idea is very obvious and at the same time if understood precisely very broad and tough. As Floridi cites historian Lynn Townsend White. “Do people have ethical obligations toward rocks?“ According to Information ethics, “all aspects and instances of being are worth some initial, perhaps minimal and overridable, form of moral respect”. It is the growth of technology making the idea more significant.

## Move fast: How Facebook Builds Software, Meyerson 2021

This book has been an instant pre-order since I've always liked Jeff Meyerson’s Software Engineering podcast. Jeff asks industry experts really great questions that are usually related to strategic aspects of software engineering. I am a huge proponent of those questions since they often predetermine the purely technical ones. I also think these questions are overlooked by folks in technology in many cases.

The book is actually a use case story of how Facebook adapted to the growth of the mobile platform and how the company managed to build and hold their position on the market. The company always balances trade-offs, product-wise, strategy-wise, cultural-wise and software engineering-wise. The book examines how Facebook dealt with some of the tradeoffs along the way in a variety of aspects of running a company, mostly related to software engineering through the lenses of Facebook ex-employees.

The move fast is not a flat phrase and actually means a thoughtful strategy that imposes quick action with possible expenses in mind.

I appreciated most of the chapters on Facebook’s product strategy. Chapters on dealing with the growth of mobile, the threat of Google+, acquisition of a cloud computing company Parse and Facebook’s culture. In these chapters, I felt the idea of a move fast strategy was present most. The more technological chapters presented information I knew, in slightly better detail. For me, the book is strongest in parts that emphasize and gives us a notion of comparison of some of the trade-off's Facebook decided to take. For example, in the early stage of the company, strategically giving priority to quick iteration at the expense of consistency in some parts of the product and not writing tests at all e.g., the user view, whereas seeking consistency in strategic business logic parts e.g., the ad manager and the development of ReactJS.

It's easy to connect with the text and who is cited there. Often when a new person is introduced, their personality and even visual traits are outlined. The book is highly readable and perhaps not too dense in information; however, the delivery is very smooth.

## HBR’s 10 must reads on managing yourself, HBR 2010

We’ve chosen this book from HBR’s The Essentials series for a first attempt of co-reading with my friend. The book is a collection of short essays that seemed feasible for our first attempt, since we read individually at our own pace and synchronize once a while on an update, reflecting the essays. If we decided to read eg. a novel at first, syncing would be more prone to problems. I was also afraid we will not share the same enthusiasm for the topic but it turned out to be a very good choice for both of us. Another reason was that I’ve seen Patrick Collison recommending this book on his website.

I think that especially nowadays we live in a world in which management competencies are more essential regardless of the job we do. Individuals at any level and even at non-managerial jobs, need to be at least aware of them since it helps them communicate and work with managers in a shared mission. Moreover, as we gain more experience, we need to focus on increasingly important tasks, and more or less, move towards managerial roles. I read those essays from this viewpoint and couldn't be more satisfied with their contents and the ideas presented.

Those ten essays are the basic essentials of managing oneself, tackling with questions like: What to optimize in life to find balance and prosper in the managerial role, how to work manage own energy with respect to peers, subordinates and self-imposed time? How to communicate and delegate and lead effectively? How to manage information overload? Most of the ideas are nowadays generally known and as they became best practices over time, they may seem a little obvious. I think that's also the reason why many people fail to realize them and oversee them. The most obvious ideas are actually usually the most subtle and hard ones. The book made me think about the ideas and explore some of their non-obvious aspects. It also stroked me to find out more info about the scholarly authors of the texts. There were names like Daniel Goleman, Robert E. Quinn, Edward Hallowell. I realized I already knew some of their work even though I didn't associate it with the authors at first.

## Mathematics: A Very Short Introduction, Gowers 2002

I always felt that my understanding of the absolute fundamentals of mathematics was very limited and it bothered me. By these fundamentals, I don't mean basic mathematical operations but the assumptions being made when thinking about mathematics in the first place.

I associate my learning and understanding of math with my primary and secondary school experiences since school is the place where I encountered math fundamentals in a structured way. In my experience I was introduced to some concepts, let's say a division operation, by showing few examples and being asked to find results for some problems which include the concept of division. I figured out what division is, and got a strong sense of it over few attempts. But not so precisely! Deep in my soul, I felt there are scenarios in which I don't know how the division behaves e.g. division by zero. Thus, I felt very uncertain and I felt I didn’t understand the concept properly but I wasn't either ready to examine it properly.

The book addresses some questions and by no means pitfalls, I’ve been personally bothered with when learning mathematics but wasn't really aware of. Especially the introductory chapters that focus on the abstract method of mathematics.

“Mathematicians do not apply scientific theories directly to the world but rather to models. A model in this sense can be thought of as an imaginary, simplified version of as an imaginary, simplified version of the part of the world being studied, one in which exact calculations are possible”.

A recurring topic in the book is that mathematics takes out the philosophical aspect and seeks only the usefulness of mathematical concepts.

Seeking ‘what a mathematical concept does’ rather than ‘what a concept is’ is argued to be more effective in understanding it because (as a slogan says) “a mathematical object is what it does”. The abstract method of mathematics takes this attitude.

Knowing that the math community understands math with usefulness in mind, edge cases and uncertain concepts are much clearer to grasp and the uncertainty goes away (at least for a while!). For me, algebra is better understood after understanding abstract algebra since many edge cases like division by zero may not be apparent without understanding its design in the first place.

In the same spirit, the rest of the book discusses proofs, how math deals with infinity, a basic understanding of geometry and estimations. I will leave here my notes on these.

### Some highlights

Proofs build on axiom laws which are usually simple and may be derived from first axioms (even more simple). Mathematicians publish proofs in reasonable detail and do not show every derivation and connection to first axioms. If the community does not understand some part of a proof, they publish more detailed steps until they convince the community or find a mistake in their reasoning.

Concepts with dimensions other than integers are possible (Koch snowflake) and may be useful.

Euclid’s elements (300 BC) set 5 axioms and build modern geometry on them:

- Any two points can be joined by exactly one line segment.
- Any line segment can be extended to exactly one line.
- Given point P and length r, there is a circle of radius r with P at its centre.
- Any two right angles are congruent (we can slide them together and observe they are the same).
- A line N intersects two lines L and M. if the interior angles on one side of an add up to less than 180, then the lines L and M intersect on that side of N (eventually).

A parallel postulate can be derived from the 5. (however, its derivation from 1-4 is a matter of discussion). Using these axioms and the parallel postulate, we can eg. show, that the inner angles of a triangle add to 180. Immanuel Kant (18th century) devoted a part of Critique of Pure Reason to the question of how one could be absolutely certain about Euclidean geometry. Parallel postulate does not hold on spheric geometry (primary school teacher’s example!) or hyperbolic geometry. In hyperbolic geometry, distances at point P are larger by normal distances by 1/d^2, where d is the distance from P to the boundary of the circle. (If you move at constant hyperbolic speed, you would appear to move more and more slowly as you approach the boundary of the disc).

Estimates and approximations are essential to mathematics since its often the only way to get useful grasp of a problem and it may be extremely hard to get exact results. Sometimes, founding the bounds or limits of a potential problems results is very useful.

- Knowing or proving that approx. result and actual is equal up to a certain difference (additive constant) or has certain ratio (multiplicative constant).
- Number of digits of in operations give us too very good estimates since we can deduce upper and lower bounds of the actual result without doing computations (k digit number times n digits number gives result between 10^(n+k-2) and 10^n+k so 10^(n+k-1) gives estimation that can differ 10-times higher or lower).
- Mathematicians understand exponents, squere roots and logarithms and use them to articulate their estimates (as in computer science algorithms). Its good to know that square exponent gives approx 2 times more digits, square root gives number with approx. half number of digits, cube root with third number of digits and so on. Logarithm log10 gives approx. the number of digits. Natural logarithm ln can be estimated by log10 times 2.3.

Recommended sources:

- Russel and Whitehead - Principia Mathematica, contains proof for 1+1=2.
- Authors website contains interesting questions like What is `solved' when one solves an equation?