The Logic I: Tools for
Logic I: Tools for Thinking is a full-year logic course
offering in-depth coverage of a broad range of
useful logic tools at a beginner-friendly pace. It can
be used as an introductory or second-year logic textbook
for students in grades 8 or 9 and above (and some 7th
graders). Tested and proven in homeschool, co-op
and Christian school settings.
What do users say about the program?
“I would use Birkett's Logic again in a heartbeat."
—Peter Lipsy, co-op teacher
“A wonderful guide through some challenging waters."
—Karen Carlson, homeschooling mother
“An excellent introduction for the junior-high or high-school student"
—Jessica Kaiser, Christian school teacher
“Through this course, good study habits and deeper thinking skills are acquired."
—Becky Genberg, co-op teacher
Why do users value Logic I: Tools for Thinking?
- accessible, engaging, precise, accurate
- the formal and informal logic tools most useful to beginning students and how and when to use them
- no logic background required
- humorous and serious examples engage students
by drawing from a wide range of subject areas
- helpful Teacher’s Manual with answer keys, teaching tips,
and enrichment material; unit test packet included
- thoroughly Christian approach to logic—not antiquated, simplistic, or combative
For a closer look at the curriculum, including fuller excerpts from user testimonials, read on. For further details on a specific volume, and to order, visit the product details pages for the student textbook or the teacher's manual with test pack.
For a summary of program content, take the guided tour with sample chapters.
in a nutshell | why study logic? | can I really teach logic?
is this program what I'm looking for? | are my students ready?
what methods does this program use? | it's traditional; is it boring?
frequently asked questions | final thoughts
guided tour with sample chapters | guarantee | to order
Truth or consequences
You probably already know that logic has something to do with thinking clearly. But why does clear thinking matter? Because truth matters! In seeking a logic program, you are on a quest to equip a child with tools that will help him or her discern between true and false, accurate and inaccurate, sound and unsound, in a wide variety of situations where getting it right matters.
Better tools . . .
We all have logic intuitions, but they are often inadequate for the thinking problems that we face. Better tools are needed! Logic has the tools we need for better thinking, grouped into two important tool types, formal and informal. We think it's important to equip students with a working knowledge of both.
Logic I: Tools for Thinking presents formal and informal logic tools in a cohesive, up-to-date framework. You don't get a jumble of logic techniques, but
a carefully chosen set of tools for thinking. And you learn which tool to use when.
Don't butter toast with a sledgehammer
Hammers and screwdrivers are great, but only if you know what they are, what they do, and how and when to use them. Use them for the wrong job and at best, they won't work, and at worst, they will do harm. Try using them to butter toast or do brain surgery!
Likewise, logic consists of many tools. You want the right logic tools in your kit and you want to know which tool to choose for a given job.
That sounds obvious . . .
But there's a catch
Since the tools of logic work on ideas, and since ideas are framed in language,
an effective logic textbook must deal with the interface between the tools of logic and the sentences of human language. Logic I: Tools for Thinking does just that.
Many logic texts neglect this interface, leaving a critical gap in the student's understanding.
The stakes are high
Why does this gap matter? If you can't connect language to logic, then you can't use logic to help you handle ideas. You won't know which logic tool to pick up and use if you don't understand the interface between language and logic.
This is critical, because the stakes in logic are high. Choose the wrong tool for the job, or use no tools at all, and what happens? You will believe—and maybe even teach—that false things are true and true things are false.
So logic matters because truth matters. The stakes are high and the tools have to be right. And there's a lot of ground in logic to cover, so it will be more than a tool or two. But there's one more thing.
Grown-up toolkit, young person pacing
A textbook for young people has to work for . . . young people. There's no point in covering lots of great logic tools if you lose the student in the process. Broad topic coverage with young person pacing—is that possible? What do users say about Logic I: Tools for Thinking?
"An excellent introduction for the junior-high or high-school student. The material is introduced slowly and progressively."
Jessica Kaiser, Christian school teacher
"A definite winner.
The introductory, foundational material is solid (precise and broadly applicable) but totally accessible as well (my students had no classical education background). At the end of the course I was astounded at the number of arguments that could be understood and usefully evaluated using just the tools in this one textbook."
Peter Lipsy, co-op teacher
In-depth coverage of a broad selection of useful logic tools at a beginner-friendly pace? Yes, it is possible!
To read more about the content of the program, see the guided tour with sample chapters.
Logic study can help your son or daughter prepare for almost any calling.
To see why this is, it's helpful to consider a definition of logic. Logic is the science of correct reasoning. We all have to reason every day, after all, and the study of logic helps us to reason more reliably. How does logic help us reason correctly? It's a toolkit that helps us evaluate truth claims by enabling us to test whether a given conclusion really does follow from a given set of assertions.
That may sound abstract, but if you've ever said to yourself "well, that doesn't follow from what he just said," or "just because that's true, it doesn't mean this," you've been using logic to avoid being taken in by false reasoning. We all have logic intuitions that enable us to think in this way, but the study of logic gives us more powerful and more accurate tools that enable us to discern "what follows" much more reliably.
Why do we need these tools? Because truth and falsehood matter. Because accuracy and error matter. Because holding to the truth and seeing through deception matter.
Logic can help a pastor see through the twisted claims of a cult. Logic can help a college student not to succumb to false worldviews. Logic can help an auto mechanic diagnose a car problem efficiently and accurately. Logic can help a detective unravel a case; can help a computer programmer debug a systems problem; can help a civic leader persuade a community to avoid a foolish mistake; and logic can help a Mom evaluate curricula and train her children for any calling.
Is that a startling list? People in these callings don't relate to truth identically, but in all of these callings the ability to hold to or arrive at the truth by reasoning accurately is an invaluable asset.
Since logic is helpful in so many different callings—and that list was just a sample— most children will benefit from the study of logic.
Logic study will benefit your children in their school years as well—and not just in logic class—because logic sharpens thinking skills in general, teaching the value of precise and orderly thought in solving multi-part, multifaceted problems.
"I had many parents come to me during the end of the school year and tell me the changes they saw in their children—better study skills, taking the time to think through things more, being diligent in working through harder tasks. They learned more than just logic!"
Becky Genberg, co-op teacher
And whatever calling your children will one day enter, logic is valuable because God's word and false, destructive philosophies come to us in the form of claims and conclusions, "this-is-so's" and "therefores," and logic helps us judge truth claims by equipping us to analyze trains of thought. Logic does not stand above the truth of God's word and can never replace knowing God's word well, but logic can help us understand and remain in God's truth, and prevent us from falling prey to error.
Only boys need to take logic, right?
We understand why someone might think this, but we respectfully differ.
We do believe, as many of you do, that men and women are not identical and were not created by God to fulfill identical roles in his world. We honor the role of a wife and mother; we understand that many girls will grow up to fulfill this role; and we view this as an excellent thing. We still believe daughters benefit from the study of logic. Why? Because if you are reading this page, most of your daughters will experience not only marriage and motherhood, but also college and wage-earning singleness. And logic study can be helpful to your daughter in each of these stages in her journey through life. For more on this topic, see Why girls should study logic.
Yes! This book has been used successfully for more than five years in a variety of Christian schools, homeschools, and co-ops. Some of the teachers had studied logic previously; some had not. You will succeed with Logic I: Tools for Thinking—even if you have no logic background—if you're interested in learning logic and willing to do the exercises yourself. You can learn and teach at the same time.
Only Dads can teach logic, right?
Dads can teach logic, and it's a great thing for Dads to do with and for their children. We encourage more Dads to be involved in homeschooling their children. But that's not always possible, and Moms can teach logic too. Many Moms have successfully taught Logic I: Tools for Thinking. How did they do it?
"I remember my fear of tackling such a subject the first time through. I had never had any formal logic! How could I guide my students through it? Yet, after working through the first chapter with my daughter and doing the exercises side by side, I gained courage to look at chapter two, and then chapter three, and on and on. Each chapter helpfully prepares you to take on the next chapter. We just finished chapter 27 yesterday and it is encouraging to look back and realize all that we’ve covered and learned!"
Karen Carlson, homeschooling mother
If you're a Mom convinced of the value of logic, give it a try. Begin at the beginning, take it one page at a time, and learn right along with your children. You'll be glad you did!
"I would highly recommend this curriculum if you are pursuing a challenging logic course. This was actually the first logic class that I ever took. So I learned right along with the kids! It is a challenging course, but I enjoyed it. With diligence and perseverance, mastery of the material can be gained. Through this course, good study habits and deeper thinking skills are also acquired."—Becky Genberg,
If you're looking for a substantial program that covers a wide range of logic topics, Logic I: Tools for Thinking is for you. It covers both formal and informal logic tools, and it provides a full year of logic instruction, with enough material for several class periods a week. See Frequently asked questions for more lesson planning information.
Formal and informal
You've encountered the terms formal and informal elsewhere on this page, and you may also have seen the terms deductive and inductive in discussions of logic curricula. How are these terms related? Formal and informal logic tools are used on two different kinds of reasoning: deductive and inductive. Most often formal tools are used on deductive reasoning and informal tools on inductive reasoning. Both kinds of tools are important and both types of reasoning are important, so Logic I: Tools for Thinking covers both.
"[The program works] step by step through one of the most useful modern formal logic systems, the sentential calculus. After the sentential calculus is developed, the last quarter of the textbook provides a fun and welcome break-away from formal logic to introduce informal arguments and how to analyze them (these are arguments the students hear on a daily basis)."
Peter Lipsy, co-op teacher
So formal tools are usually used on deductive reasoning and informal tools on inductive reasoning, but just what are deductive reasoning and inductive reasoning, anyway?
Certain or reasonable
To oversimplify, deductive reasoning is reasoning in which the conclusions follow with certainty if the reasoning is compelling, and inductive reasoning is reasoning in which the conclusions are probable or reasonable if the reasoning is compelling.
Inductive arguments are heard very commonly in everyday life because most conclusions someone wants you to reach are at most probable or reasonable, rather than certain. However, important deductive arguments occur in everyday life too, and in addition, deductive reasoning figures prominently in disciplines like math and computer programming. A complete logic course needs to cover both types of reasoning along with the formal and informal logic tools you need to evaluate them.
Minding your p's and q's
How do you know whether a logic program covers both of the important divisions of logic? The formal logic tools which are often used in evaluating deductive arguments make liberal use of symbols and p's and q's (or A's and B's) to reduce human language to a more compact form which is easier to analyze using formal logic methods. (It's a convenient shorthand or abbreviation system, which you'll learn easily with the help of a text that begins at the beginning.) Much analysis of inductive arguments, on the other hand, is performed by informal methods, largely without symbols.
The table of contents of a logic text may be impenetrable if you aren't familiar with all the specialized terms you'll see there, but you can use your knowledge of p's and q's to discern what broad areas a logic book covers. If you see a chapter with many symbols in a logic text, then suspect formal tools and deductive arguments. If you see a chapter with few or no symbols, suspect informal tools and inductive arguments. Leaf through an entire book and see whether both areas are covered.
Of course, you can purchase programs devoted to one area or the other, but there are advantages to treating the areas in a connected way (in a single book by the same person!), and Logic I: Tools for Thinking offers you those benefits.
You will appreciate this program the most if
- you're a critical thinker and you want clarity of understanding
- you're interested in teaching logic as it is in the real world: not always black-and-white, true-or-false, but a discipline in which sometimes multiple answers are legitimate—and the trick is defending your answers ably
- you want to teach logic more than once a week
- you're willing to do the same homework your students do while you learn
If this describes you, then you’ll like Logic I: Tools for Thinking. If you are looking for a more cursory treatment of logic, you may prefer a different program. To read in more detail about the content of the program, see the guided tour with sample chapters.
"Having taught the material once to ninth graders and many times to seventh graders, I would say that the ninth graders probably had an easier time understanding the BOOK, but the seventh graders didn't have much trouble learning the MATERIAL. While the textbook seems to be written at a higher level, the material can easily be taught to junior-high students."
Jessica Kaiser, Christian school teacher
It’s safe to say that many eighth graders and nearly all ninth or tenth graders in the world of Christian education are ready for this book. A few will be ready in seventh grade.
How to tell when your own students are ready? Consider what they will be doing in English and math during the year you'd like to teach logic. At the school where Logic I: Tools for Thinking was developed, Logic I students use Saxon's Algebra ½ in math class (and many find it a bit too easy). This is a traditional and rigorous pre-algebra textbook. In English, they read selections from the Bob Jones 9th-grade literature anthology. They also read such works as The Hiding Place, The Secret Garden, Captains Courageous, The Call of the Wild, and The Chronicles of Narnia during their Logic I year (or the summer before). Your students should be at least comparably proficient in English and math to derive the most benefit from Logic I: Tools for Thinking. If this means waiting until grade 8 or 9 to begin, it's worth the wait!
While some students are ready in grade 7, earlier starts do require more work of you the teacher, as concepts need to be unfolded more slowly for younger students.
Logic I: Tools for Thinking is a traditional textbook. Each chapter contains detailed exposition and examples, followed by exercises and a summary of terms and concepts to assist the student in studying the chapter for the unit test. Unit tests covering about three or four chapters test both knowledge and techniques taught in the chapters.
"The exercises included provide good opportunities for practicing and reinforcing the material."
Jessica Kaiser, Christian school teacher
For a closer look, take our guided tour with sample chapters.
No! Logic, properly taught, is anything but boring. In Logic I: Tools for Thinking illustrations are drawn from a wide variety of subject areas, humorous as well as serious, to engage students' interest. Regular appearances by the Birketts' entertaining cats help keep things lively, too. And the inclusion of both formal and informal logic topics helps ensure the program's appeal to a wide range of students.
"I appreciate the wholesome content of the sentences and exercises the author provides for the student to work with. The amusing feline anecdotes that are interspersed add spice and entertainment to the logic instruction."—Karen Carlson, homeschooling mother
"I appreciate the way the author uses humor and modern, relevant exercises to keep a dry subject from staying that way."—Peter Lipsy, co-op teacher
Q: Can you give me any lesson planning information?
A: In most settings, count on one or one and a quarter years to teach Logic I: Tools for Thinking. Here are three real-life examples that will help you in your planning.
At the Christian school where this program was developed, students use Logic I: Tools for Thinking in grade 7. There are three 39-minute Logic I classes per week, and students complete 28-30 chapters—out of 33—by the end of the year. There are 36 school weeks per year. Typical class size is 12-15 students.
In two local co-ops, students use Logic I: Tools for Thinking beginning in grade 8 or above. Class is taught once a week for 60-70 minutes, and all 33 chapters are completed in one year (in one case, this means completing all 33 chapters in 30 weeks). Class sizes are smaller than at the Christian school.
In a one-on-one homeschool setting, you will likely complete the entire book in nine months, quite possibly with less teaching time per week than is required in a group setting.
Of course, the book can also be taken at a slower pace, and taught over two academic years instead, if you prefer.
Q: I want two years' worth of logic instruction for my students. Can this book be followed by another curriculum?
A: For now, we suggest the use of Introductory Logic by James Nance and Douglas Wilson (the fourth edition, not earlier editions) as a sequel. It offers some overlap with Logic I: Tools for Thinking, but new topics, as well. (Those who complete our Logic I have already covered many of the topics in Nance's Intermediate Logic, because of topic sequence differences between the programs.)
Previously in this space we suggested Martin Cothran's Traditional Logic (Book I) as a sequel to Logic I: Tools for Thinking, but with the fourth edition of Nance and Wilson, their Introductory Logic is more suitable.
Q: I've already taught one year of logic from another curriculum, but I like the look of this one. Can Logic I be used as a second-year course?
A: Yes, it can. We think you'll find it adds significantly to the treatment provided by other logic books in the Christian education market, in some cases by covering additional topics, and in other cases by covering topics in greater depth.
Q: What programs should I consider for use before Logic I: Tools for Thinking?
A: One sequence that works well for a number of users is to use The Fallacy Detective, by Nathaniel and Hans Bluedorn, and Art of Argument from Classical Academic Press, in grade 7, followed by Logic I: Tools for Thinking in grade 8.
Q: What do I need to buy?
A: In school and co-op settings, you’ll need one copy of the teacher’s manual (which comes with a test packet) and one copy of the student textbook for yourself, plus one student text for each student you’re teaching. Homeschoolers,
if you're willing to share a student book with a child, you'll just need one teacher’s manual for yourself and one student textbook for each child you are teaching. If you'd rather not share, then you will need a student book for yourself as well.
"Mr. Birkett has done a tremendous job in writing a junior-high level logic program that is a wonderful guide through some challenging waters." Karen Carlson, homeschooling mother
"I would use Birkett's Logic book again in a heartbeat. . . . It was refreshing for me as a teacher to see that my textbook's author recognized the advances in logic that have been made since the Middle Ages; the textbook did not reflect a nostalgic embrace of just one small piece of the logic pie (Aristotelian syllogisms)." —Peter Lipsy, co-op teacher
Join these satisfied users of Logic I: Tools for Thinking, and you and your students will have your thinking skills sharpened as you acquire a valuable set of tools for thinking.
For a tour of program content and links to sample chapters, please visit our guided tour with sample chapters.
You may return your purchase for any reason within 60 days for a full refund of your purchase price. Please see our policies page for more details.
To order, please visit the product details pages. We use PayPal for secure and convenient ordering, or you can print an order form and mail us a check. For details on our order fulfillment process, please see our policies page.
We look forward to hearing from you, and may God bless you on your logic journey!