Original Site Title: Appetizers and Lessons for Mathematics and Reason, June 1995 to April 2012. New site title:
Logic and Mathematics Skill & Concept Building Site Map || Français: 26 pages
for college students, gifted teens, home-tutoring and K1-12 schooling, with chapters on Logic
and Pattern Based Reason to inform and amuse thinkers and avid readers, studying or not. Enjoy.

Logic mastery strengthens comprehension and improve home, work & study habits.
Logic 5 Chapters Arithmetic 10 Steps Algebra 12 Starter Steps & 5 Advanced Steps
Work & Study 23 Tips Geometry 15 Steps Calculus 70 Lessons

Ages 15+: Why study slopes Polynomials Quadratics Why factor polynomials Logarithms Functions
What is similarity Euclidean geometry leanly Coordinates + complex no.s Vectors DC Electric Circuits

Ages 12+: Prime factorization Written work formats Decimal place value Extend arithmetic skills orally
What is a variable 5. Fraction Operations by Raising Terms Solving Linear Equations: Take I Take II


Online Volumes: 1 - Elements of Reason, 2 - 3 Skills For Algebra, 3 - Why Slopes and
More Math
, 1A - Pattern Based Reason, 1B - Skill Development Principles + Troubles
Forewords + leading chapters give original reasons, still valid, for site content & growth.

About: Site material shows how common troubles stem from steps too large or missing. Site material may develop critical thinking, improve reading and writing, and build mathematics and pattern based reasoning skills. Online Volumes 1, 1A and 2 give avid readers in school and out the best places to begin. If one site element is not to your liking, try another. Each is different. Many are unique

Teachers & Tutors: This December 2011, 5-phase framework offers a context for mathematics & logic education. Phases 1 to 3 may focus on skills with actual or potential local value for adult & daily life. College-oriented phases 5 & 4 focus on calculus & preparation for it. Phases 1 to 4 may also serve trades & professions not dependent on calculus. Reform: look before you leap - plan all in detail first.

Site Review: Math resources ... span ... arithmetic, logic, algebra, calculus, complex numbers, and Euclidean geometry. Lessons and how-tos .... provide a good foundation for high school and college ... mathematics. Read more.

Location: Site Entrance < Volume 2 Three Skills For Algebra << Chapter 3 Chains of Reason

[1] [2] [3] [4][5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42]


Chapter3, Chains of Reason

Introduction

This chapter shows how reliable rules and patterns can be directly employed one at a time, or one after another, to get conclusions or further reliable rules and patterns. The question of what rules are reliable is considered in the following chapters.

Rules used to get or suggest conclusions are called implications. Just as there are methods for adding and multiplying numbers carefully, there are also methods for using implication rules by themselves to get conclusions. There are also methods for linking, threading and chaining implication rules together to get more implication rules. This chapter uses examples to explain two basic ideas:

  1. how to directly use a single implication rule to get conclusions, and
  2. how to link, chain or thread implication rules together to obtain or derive more rules and more conclusions.

The examples are not important (and are perhaps ridiculous) but they illustrate some rule-based methods in reason. Examples which involved real-life situations might distract from mastering these methods. That is, in real-life situations, each of us may have opinions or prejudices about what should occur. That could spoil an explanation of the use and linkage of implication rules. There is a need for neutral examples to illustrate the use of implication rules one at a time or one after another.

Arithmetic, algebra and geometry give many neutral examples for this. The examples below involve no mathematics. Bon Appetite.

Conclusions From a Single Rule
Direct and Indirect Usage

Pretend the following implication rule is never disobeyed.

Each time Suzy the cat is on the ground and Suzy sees a dog, Suzy climbs a tree and stays in it for at least five minutes.

Direct Usage

What can we say for sure when Suzy the cat sees a dog? One possible answer is that Suzy the cat stays in a tree for at least five minutes. Another possible answer is that Suzy the cat climbs a tree. A more complete answer is that Suzy the cat climbs a tree and stays there for at least five minutes. Each of these answers or conclusions is correct. The last conclusion or result is fuller and more complete than the others. It gives more information. Which answer or conclusion is wanted here depends on who is interested in what. When many conclusions are possible, we state only those conclusions of interest to us. We do not have to state the most complete conclusion. The choice is ours.

Indirect Usage

What can you say for sure if Suzy the cat has not climbed nor stayed in any tree for at least five minutes? To check your answer, you might have to remember or revisit the questions in the chapter Implication Rules. But you should do this after you have read the following words.

Linking and Chaining Two Rules Together

The examples below and in the next page show how to chain, link or connect implication rules to get information and conclusions. The examples in themselves are not important. The information in them is silly. But these examples just show how to put implication rules together. So read on, with patience.

  • Every time Suzy the cat climbs a tree, it gets stuck in the tree
  • Every time Fred the dog visits the park in which Suzy the cat lives, Suzy climbs a tree.

By linking or chaining these implication rules, we can make three conclusions:

  1. Whenever Fred the dog visits the park where Suzy the cat lives, Suzy climbs a tree.
  2. Whenever Fred the dog visits the park where Suzy the cat lives, Suzy gets stuck in a tree
  3. Whenever Fred the dog visits the park where Suzy the cat lives, Suzy climbs a tree and gets stuck.

Each of these conclusions is correct. Each conclusion gives a new implication rule which we could use in our reasoning process. The third implication rule is the most informative. It contains the most information. When we view each correct conclusion as a possible destination for our reasoning process, we may sometimes select our destination.

Putting Several Rules Togethe

We can chain or link not only two but also several implication rules together. This sometimes yields useful, new information. As an exercise, we ask the question: What happens whenever Fred the dog visits the one-tree park? Several answers are possible. Some have more details than others. All are correct. To answer the question, assume or pretend the next five implication rules are never disobeyed. Further, assume that Suzy the cat lives in the one-tree park.

  1. When Suzy the cat climbs the tree in the one-tree park, Suzy gets stuck in the tree.
  2. Each time Fred the dog visits the one-tree park, Suzy the cat climbs the tree.
  3. Every time Charles the human visits the park, Charles sits on a bench for one hour.
  4. Whenever a cat climbs the tree in the one-tree park, the five birds living in the tree fly around in the park.
  5. Each time birds fly around in the park, sensible worms go underground.

All the information has been stated. We start our reasoning process. That is, we will answer the question: What happens whenever Fred the dog visits the one-tree park?

To answer the question, suppose or assume Fred the dog visits the park. Then from the implication rule (2), we see that Suzy the cat climbs a tree. Next, from the implication rule (1) we see that Suzy the cat gets stuck and from the implication (4) we see that birds fly around the park. Finally from the implication (5), we note sensible worms go underground.

We could list all that occurs when Fred the dog visits the park. Or, we could state only those results of Fred's visit to the park which are of most interest to us. The choice is ours. For instance, one of our possible conclusions follows:

If Fred the dog visits the park then sensible worms go underground.

This conclusion is not of interest unless you are a fisherman (or woman) looking for worms, sensible or not, for use as bait. The conclusion selected and stated here hides the reasoning process. That is, it hides the chain of implications leading to it. Our last conclusion does not mention the intermediate events where a cat climbs a tree and birds fly around the park.

The long path by which we get conclusions shows that implication or rule-based thinking can lead to surprising results. These surprising results are true if the initial implications are also true.

In the long path by which we got the conclusions, the information in the third implication (3) about Charles the human is not used. The conclusion we reached is independent of implication (3). In fact, without further information, I see no way of linking the rule about Charles with the other rules. The third rule is extra information. It can be ignored.

In answering questions, we often have extra information. Indeed, you can imagine the five rules given above are stated in random positions among a list of twenty, or hundred and twenty rules. An answer to the question

What happens when Fred the dog visits the one-tree park?

now depends on finding the rules in the list which can be used. This is a game of hide and seek. So we have to be selective, observant or fussy in deciding or seeing what information leads to our conclusions.

The scenery or route by which a conclusion is reached may contain as much useful information as the conclusion itself. A conclusion may contain a fraction of the information we could have stated or written. Being aware of the route or proof by which a conclusion is attained will sometimes suggest how more conclusions can be reached. This awareness is often more important that any conclusion we state because it allows us to state more conclusions, as needed.

Mathematics students take note. Remembering the route taken in solving a problem is worth more to the development of skills than remembering the solution.

Deductive, Inductive or Empirical Reason

Deductive reason uses or chains together supposedly (or preferably) never-disobeyed implication rules to suggest, to make or to reach conclusions. See the examples above. The implication rules in question may come from assumptions. The assumptions may be tentative.

The phrase inductive reason has one role in mathematics and another outside of mathematics. To induce (or induct) literally means to draw or extract. When you see a rule or pattern that no one has suggested, you are extracting or drawing that pattern from your observations. This process of recognizing rules and patterns that may hold, accidentally or not, is called inductive reasoning. Inductive reason outside of mathematics refers to the identification and recognition of rules and patterns from data and observations. Here rules and patterns may hold accidentally.

Reason which relies on a single or several, experience-found, rules and patterns to arrive at conclusions is called empirical. The underlying problem of inductive, empirical reason is to extract (infer, draw, induct or identify) from experience, in particular, data and observations, rules and patterns not satisfied merely by accident and which appear to be reliable. Self-deception needs to be avoided here.

Inductive reason inside mathematics refers to another process, namely, the extraction or drawing of conclusions from ladder-like chains of reason. See the next chapter for a more precise image or explanation. The rules or assumptions here are usually so certain, that we deliberately ignore the experience-based origins of mathematical reason.

Criteria for the recognition of reliable, non-accidental rules and patterns are described later in chapter 16, Origin of Rules and Patterns .

Road Safety Messages and Questions: When and why should you face traffic when walking along a road or cycle path? Is it a good idea to hang limbs outside of cars etc? What gives more protection in a crash: a car, motorbike or bicylce?

Death Penalty: How Texas sent an innocent man to his death - The wrong Carlos.

For home-tutoring or -schooling, or for schools or colleges with course content control: Secondary Mathematics for Ages 11+, A Practical Approach.

May 2012, Composition Starting: Pre-School and Primary Mathematics - Quantitative Skills, An Intellectual View, Feedback Welcome:

The 8 Most Popular Site Inlinks

20 Times Table - the most popular site page - popular pages - unexpected.
Fractions & Ratios - with lesson on raising terms to introduce & justify times, division & comparison as well addition & subtraction
Parent Center - See below
Volume 1, Elements of Reason - Intro to all site books.
What is a Variable - best for ages 13+
Written work formats for Arithmetic and Algebra - a skill method and standard!
Complex Numbers Visually - best for ages 13+
Natural Logs, Exponentials, Powers, Roots

Division of Labour: This site offers advice and directions with pointers to resources elsewhere, if known, when they help or lessen the need to write more.

Parent Center: Help your child or teen learn:

Parent-friendly Work Booklets for ages 3+ to 13 Use these or others to check or build skills. Other booklets are available but these booklets allow parents unsure of themselves in mathematics to help their children. The selection acquired in Canada is published in the USA. So it has a US orientation. In retrospect, the selection shows parents what to check with the booklets or by other ways, the choice is theirs. But in retrospect, the selection does not cover integral and fractions liquid weights and measures - ask the publishers to correct that! For ages 9 to 12 say, parents may compensate by showing boys and girls how to use weights or mass, and further measures in food preparation. Beyond that children may be shown how to measure and calculate angles, lengths and areas [proportional amounts too] directly or by using maps and plans drawns to scale. Learning how to gather and measure all the ingredients, pots and pans for a dish or a meal, along with cleaning up sets the stage for like activities or experiments in science courses, and in developing organizational skills, gives boys and girls a head start. Good luck. At the other extreme, more comprehensive than light, if your motto is McCainian: drill, drill, drill then Toronto mathematician and actor John Mighton's jump math organization has jump math workbooks for at least grades 3 to 8 for at-home and in-school use - training sessions for teachers available. Jump math has been expanding to cover older students. Jump Math Samples: plus Fractions for Grades 3-4 & Grades 5-6 [Read] Free Resources grades 1 to 8 [unread - likely to be good]. and

Mathematics Skills For Ages 3 to 14 - technical!

Skills with take home value - A few ideas

Basic skills include time-date-calendar Matters; money matters; map, plan and scale diagram matters;counting, measuring and figuring; decision making with logic and likelyhood; being careful and being aware of the domino effect of mistakes; reading and writing with precision.

Is your child able to add, subtract and multiply amounts of money, work with fractions, work with clocks and calendars, work with maps and plans, and measure length, weight-mass and volume? Schools may promote your son or daughter without providing basic skills in reading, writing and arithmetic.

Arithmetic and Number Theory Skills

Algebra Starter Lessons

1 Working With Sets
2 Formula Forward Use - Evaluation
3 Solving Linear Equations - Skip first step with students able to solve 1 eqn in 1 unknown.
4 Computation Rules and Function Notation
5 Real Numbers
6 More Less Greater Than Inequalities and Comparison
7 Axioms Logic and Equivalent Equations
8 Unifying Theme For Algebra
9 Proportionality Backwards and Forwards
10 Examples of Algebraic Reasoning
A Origins of Counting and Figuring Methods
B Real Numbers Extrinsic Development


Site coverage of formuala evaluation format, of computation rules and axioms, and of the forward and backward use of formulas and proportionality relations lessens the amount of natural talent needed to understand and explain algebra.

Geometry - maps plans trigonometry vectors

1 Maps Plans Measurement
2 Euclidean Geometry - Constructions + extras
3 Cartesian and Polar Coordinates
4 Lines and Slopes Take 1
5 What is Similarity
6 Trigonometry first steps
7 Complex Numbers
8 Unit-Circle Trigonometry
9 Lines and Slopes Take 2 with tangent function
10 Intersecting Straight Lines and Transversals
11 Parallel Straight Lines and Transversals
12 Function Translating and Rescaling
13 Vectors
14 Degrees to Radians and Radians to Degrees
15 Arc or Inverse Trigonometric Function

Pre-Teen and young teen mastery of skills and practices which should be common with map-plans-diagrams drawn to scale, contour interpretation included, has actual or potential take-home value for daily- and adult-life in solving routine problems. Elevating some practices to principles, axioms or postualates, provides a base for analytic and Euclidean geometry, an analytic view of similarity, and an efficient mastery of trigonometry and complex numbers. Right triangle trigonometry provide an analytic alternative to solving geometric problems by drawing diagrams to scale.

More Algebra

Natural-Logarithms Exponentials Powers Roots
Five Polynomial Operations
Quadratics Geometrically
Functions
5 Factored Polynomial Sign Analysis Examples
Rewriting algebraic substitution as function substitutions

The first topic leads to a full high school level theory for the forward and backward mastery of growth and decay models and for definition, range and domains of radicals, roots and powers. The next two topics make quadratics and polynomials easier to learn and teach. Site coverage of functions turns vertical and horizontal line rules into computation methods for evaluating functions.

70 Calculus Starter Lessons

Calculus Lessons Elsewhere:

  1. How to Ace Calculus: Street Wise Guide - Mostly Text.

  2. Flash Video for Calculus Phobics

They cover basic topics in ways likely to complement your notes, your textbooks and site material. When Goldilocks trespassed in the house of the three bears, she found three bowls of porridge, two not to her liking, and one just right. Different bears have different tastes. As invited guest here and elsewhere, if one or more explanations is not to liking, try another. It may be better or just right.

Unsolicited Advice

Learning to do and high marks if it comes to easy is often deceptive - light rather than deep. For that reason, students with learning difficulties determined not to let it get in their way may go deeper and farther than those with none. High marks, if the come easy, may be deceptive - provide a too light and not a deep mastery. That could have been your problem in secondary school, one that leads to comprehension shock or difficulties in calculus and more generally in the first year of college. Bon Appetite.


Return to Page Top

Location: Site Entrance < Volume 2 Three Skills For Algebra << Chapter 3 Chains of Reason

[1] [2] [3] [4][5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42]


Logic-Reason for all
Careful Thinking
Chains of Reason
Mathematical Induction
Responsibility
Bodies-of-Knowledge

Arithmetic - Ages 10+
1. Deciml Place Value - fun
2. Decimals for Tutors
3. Prime Factors - quickly
4. Fractions + Ratios
5. Arith with units - science

Geometry
1 Maps + Plans Use
2 Euclidean Geometry
3 Rct +Polr Coordinates
4 Lines-Slopes [I]
5. What is Similarity
Algebra Starters - the base
1. Better Work Format
2. Solve Linear Eqns
3. Computation Rules
4. Axioms, Item 3 Viewpnt
5. Formulas Backwards
More Algebra
Logarithms-ax & m/nth roots
Five Polynomial Operations
Quadratics Geometrically
Functions || Vectors too
Arith. Skill Check+Answers
Calculus Prep/Preview
What is a Variable
Why study slopes
Why factor polynomials
Complex Numbers
Limits + Continuity

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