34.1Learn principles, not procedures

“As to methods there may be a million and then some, but principles are few. The man who grasps principles can successfully select his own methods. The man who tries methods, ignoring principles, is sure to have trouble.” – Ralph Waldo Emerson

E ective problem-solvers always reason from fundamental principles, rather than follow memorized procedures. Following this logic, the wise strategy for any student learning how to solve any type of problem is to internalize as many general principles as possible, and to connect common threads of principle to di erent applications and scenarios.

A good way for any student to self-check that their focus is indeed on principles rather than procedures is to continually ask themselves if they are able to explain why what they have learned is true. It is one thing to be able to explain what you have learned, but it is quite another to explain why your new knowledge is valid. “Why” may be the most important question you ever ask, and you need to ask it often.

34.2Active reading

Learning from reading printed text is a kind of problem-solving activity it is own right. The problem is how to acquire new information from the pages of a book, and the solution requires active engagement of your mind as you read. This is often more di cult that it may seem at first, especially when the subject matter is complex and/or the source text is poorly written. Given the fact that much more technical information is available in text form than in any other format, and also the fact that continuous learning is absolutely essential in the field of instrumentation, active reading is an indispensable tool for student success as well as for continued professional growth in the field of instrumentation.

34.2.1Don’t limit yourself to one text!

A very common mistake made by struggling students is to limit themselves to the reading assigned by their instructor(s), when better books might be available. If homework assignments are given from a particular assigned text, it is understandable why a student might think this is the only appropriate text to use. However, textbook selection is an imperfect process, often influenced by factors other than optimal learning (e.g. instructor bias, publisher influence, etc.). Sadly, textbooks are sometimes chosen not on their merits as a learning resource but rather by whether or not the textbook comes complete with pre-made exercises and examinations to be used in class (thus relieving the instructors of much work creating these on their own). As a student you must take responsibility for your own learning and seek the best books available for learning, even if this means only using the assigned text as a source of homework problems!

Thanks to the internet, searching for high-quality books is very easy. Not only may you peruse titles and reviews, but many booksellers also allow limited access to these texts online so you can see firsthand how the books are written and decide whether or not each book would suit your needs.

If you are a student and you approach your instructor asking about other texts to read on the subject, you may find your instructor doesn’t like the assigned text any better than you, and has alternatives ready to suggest. This is often the case in courses where the text has been selected by committee.

If you examine the personal library of any highly competent technician or engineer, you will likely find multiple books covering the same topics. Building your own collection of useful texts for learning is a sound strategy. Not only will you find yourself referencing these books throughout your career, but you will find their multiple explanations of common concepts an easier way to learn than by limiting yourself to just one point of view.

34.2.2Marking versus outlining a text

A practical and common method to increase engagement while reading is to “mark” the paper pages of a book with notations, the idea being to note points of interest and thereby stimulate thinking as you read. For a brief primer on this subject I recommend Mortimer Adler’s essay How to Mark a Book.

We will begin our exploration of active reading with an example taken from page 101 of the classic text The Measurement of High Temperatures written by George Burgess and Henry Louis Le Chˆatelier in 1912. One reason for choosing such an old text is that the style of writing adds another challenge to the task of reading. For those already familiar with the subject of temperature measurement, the archaic writing style will help give you the perspective of a new student, encountering something unfamiliar for the first time:

CHAPTER IV.

THERMOELECTRIC PYROMETER

Principle. -- The junction of two metals heated to a given temperature is the seat of an electromotive force which is a function of the temperature only, at least under certain conditions which we shall define further on. In a circuit including several different junctions at different temperatures, the total electromotive force is equal to their algebraic sum. In a closed circuit there is produced a current equal to the quotient of this resultant electromotive force and the total resistance.

Experiments of Becquerel, Pouillet, and Regnault. -- It was Becquerel who first had the idea to profit from the discovery of Seebeck to measure high temperature (1830). He used a platinum-palladium couple, and estimated the temperature of the flame of an alcohol lamp, finding it equal to 135o. In reality the temperature of a wire heated in a flame is not that of the gases in combustion; it is inferior to this.

The method was studied and used for the first time in a systematic manner by Pouillet; he employed an iron-

platinum couple which he compared with the air thermometer previously described (page 61). In order to protect the platinum from the action of the furnace gases, he inclosed it in an iron gun barrel which constituted the second metal of the junction. Pouillet does not seem to have made applications of this method, which must have given him very discordant results.

Edm. Becquerel resumed the study of his father’s couple (platinum-palladium). He was the first to remark the great importance of using in these measurements a galvanometer of high resistance. It is the electromotive force which is a function

101

This is the original text as it appears on page 101 of the book. Next, we will explore di erent ways of “marking” the text, as if we were a new reader to this subject.

The most rudimentary method of marking a book consists of underlining and/or highlighting with a felt-tipped pen:

CHAPTER IV.

THERMOELECTRIC PYROMETER

Principle. -- The junction of two metals heated to a given temperature is the seat of an electromotive force which is

a function of the temperature only, at least under certain conditions which we shall define further on. In a circuit including several different junctions at different temperatures, the total electromotive force is equal to their algebraic sum. In a closed circuit there is produced a current equal to the quotient of this resultant electromotive force and the total resistance.

Experiments of Becquerel, Pouillet, and Regnault. -- It was Becquerel who first had the idea to profit from the discovery of Seebeck to measure high temperature (1830). He used a platinum-palladium couple, and estimated the temperature of the flame of an alcohol lamp, finding it equal to 135o. In reality the temperature of a wire heated in a flame is not that of the gases in combustion; it is inferior to this.

The method was studied and used for the first time in a systematic manner by Pouillet; he employed an iron-

platinum couple which he compared with the air thermometer previously described (page 61). In order to protect the platinum from the action of the furnace gases, he inclosed it in an iron gun barrel which constituted the second metal of the junction. Pouillet does not seem to have made applications of this method, which must have given him very discordant results.

Edm. Becquerel resumed the study of his father’s couple (platinum-palladium). He was the first to remark the great importance of using in these measurements a galvanometer of high resistance. It is the electromotive force which is a function

101

Here you see how the reader has highlighted the paragraph introductory words in yellow ink, underlined names and dates with green lines, and underlined concepts with red lines. While such exercises may have helped the reader remain awake as well as generate cues for later cramming, it is doubtful they assisted the reader in understanding the concepts. A large degree of blame for this rather shallow and unproductive practice may be laid on instructional curricula emphasizing memorization and execution of procedures over conceptual understanding. Simply put, this is what you get when students expect to be quizzed on isolated bits of data: you get poor study habits such as this. Unfortunately, not only will this approach fail to yield deep understanding of the concepts, but it also reduces the act of reading to drudgery. When such practices are so common, it’s no wonder a great many students loathe academic reading.

The choice of highlighting versus underlining, or of one color over another, is relatively unimportant. Any process of “marking” a book merely by drawing attention to certain words within it su ers the same weakness: all you are doing is emphasizing specific words and phrases, not incorporating your own thoughts into the text. In order to be actively engaged in your reading, you must expose your own thoughts and reflections on what you read, not just emphasize specific statements made by the author. As Adler points out:

“Understanding is a two-way operation; learning doesn’t consist in being an empty receptacle. The learner has to question himself and question the teacher. He even has to argue with the teacher, once he understands what the teacher is saying. And marking a book is literally an expression of di erences, or agreements of opinion, with the author.”

The thrust of Adler’s essay is that the reader gains the greatest understanding of a text by expressing their own thoughts about what they are reading: articulating questions, drawing conclusions, linking ideas, and otherwise being an active participant in the reading process rather than a passive observer.

With this in mind, let’s re-approach the text. Instead of simply emphasizing words and phrases, we will now show how a reader may articulate some of their own thoughts on the same page:

Principle. -- The junction of two metals heated to a given temperature is the seat of an electromotive force which is a function of the temperature only, at least under certain conditions which we shall define further on. In a circuit including several different junctions at different temperatures, the total electromotive force is equal to their algebraic sum. In a closed circuit there is produced a current equal to the quotient of this resultant electromotive force and the total

resistance.

Ohm’s Law?

Experiments of Becquerel, Pouillet, and Regnault. -- It was Becquerel who first had the idea to profit from the discovery of Seebeck to measure high temperature (1830). He used a platinum-palladium couple, and estimated the temperature of the flame of an alcohol lamp, finding it equal to 135o. In reality the temperature of a wire heated in a flame is not that of the

gases in combustion; it is inferior to this. "Inferior" = "less" (?)

Why is this???

The method was studied and used for the first time in a systematic manner by Pouillet; he employed an iron-

platinum couple which he compared with the air thermometer previously described (page 61). In order to protect the platinum from the action of the furnace gases, he inclosed it in an iron gun barrel which constituted the second metal of the junction. Pouillet does not seem to have made applications of this method, which must have given him very discordant results.

Edm. Becquerel resumed the study of his father’s couple (platinum-palladium). He was the first to remark the great importance of using in these measurements a galvanometer of high resistance. It is the electromotive force which is a function

Why is this important? 101

Here you can see the focus has completely shifted away from facts and figures, and toward concepts. Note the questions raised by the reader, either doubting their own understanding of the book or the author’s assertions. These questions need not be fully resolved at the conclusion of reading. Indeed, these may be excellent topics to raise in class once the student returns to school and has the instructor’s attention. Questions should be taken as a positive sign for active reading and not as an indication of trouble: if you read a large body of prose and have no questions of your own, you probably weren’t thinking deeply enough!

If this manner of marking the text seems messy and cluttered, one may opt to make all the notations on a separate piece of paper, or even typed into a computer for later printing and retrieval.