Dave's Logic Puzzles

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Make Money Writing Logic Puzzles

by David Curran

Part I

If you have a fertile imagination and a logical mind you could make a steady monthly income writing logic puzzles.

Logic puzzles, simply, are one page mysteries that don't usually involve a crime. Readers are given a scenario with clues and are asked to methodically eliminate possibilities until the puzzle is solved. Sample Puzzle.

Because Logic puzzles are hard to put together the market is wide open. Many of the puzzles you see in magazines today are great on logic but poor on creativity. Don't get me wrong. These are logic puzzles and perfect logic is essential. But if you can combine logic with some creative writing that makes your puzzles both logical and fun to read, you could make hundreds of dollars monthly writing them.

To make money creating logic puzzles, you first need examine the puzzle magazines. You can find many logic and general puzzle magazines that include logic puzzles at most newsstands. Once you've looked the magazines over, write to the publishers for writer's guidelines. Some publishers have specific rules about how to write puzzles. And those that require grids like the one in the example will send you a template that you can photocopy and fill in by hand. So it's best to get the guidelines before you start.

The first step in creating a logic puzzle is to develop a story. For this simple example, I decided to focus on a character named Fishy who finds his mountain cabin ransacked by pack rats. There are five objects he's lost, five locations and different times when he finally located the missing items. The object for the puzzles solver is to match each lost item with its location, and the time fishy found it.

Once you have your idea you are ready to work on your scenario. Some people like to solve the puzzles without a solution grid Example Puzzle; they use only the story as a reference. This means that everything they need to know about, to solve the puzzle has to be included in the scenario. In the case of my example this means all the object names. All the locations and all the the times are mentioned in the scenario.

In the scenario you also need to mention any distinctions important to solving the puzzle. For example, in one of my puzzles I wrote in the scenario:

Three of the spirits were predators, Bear, Puma, and Wolf. And two of the spirits were large animals which provided sustenance for the tribe, Buffalo and Elk.

(Back to "First I write the Scenario" if you got here from there.)

These differences were important because I used the distinction between predators and non-predators in the clues.

Once you've got your scenario done you work out what happened. The process is not unlike writing a mystery. Just make a solution table (EXAMPLE) and fill it with the characters (or whatever) in your story. Note in the example that each lost item is matched up with one and only one location, and one time.

Some publications require that you write for guidelines--and/or send in only one or two puzzles at first. This is because it is tough of editors to have to read puzzles by people whose logic is faulty. If your puzzles are good you'll be invited to send as many as you like.

Remember though, that the scenario is a place for details not for clues.  All clues must be separate from the scenario.

Clues usually come with a solving gird, SOLVING GRID a table for true and false facts the readers can check off as they work through the puzzle. Solving grids are not always necessary but as a writer its' better to have them as they'll help you with proofing the puzzle. With the gird, if you read in the first clue one that

Fishy discovered an object hidden along with sticks, and mattress stuffing in the stove sometime before noon.

you can mark off Noon and 1PM from the gird on the Stove's row.

The next step is writing the clues. Here writing really comes into play. The best writing weaves your clues into a story, and the better you are at that the better you are selling your puzzle.

Once you have your solving grid you can begin your clues. Logic is essential here, but you may not want to make your puzzles too easy. Not only do publishers usually need more complex puzzles than they do easy ones, but if the puzzle is too easy it it will take longer to sell because publishers usually have more easy clues on hand.

Keep in mind that the clues must give enough information for the reader to solve the puzzle logically. And that there can be only one logical conclusion.

What do I mean by logically.

One important meaning is that the clue must not be related to any knowledge outside of what is in the puzzle. That is the reader should not have to know anything other than what is in the puzzle. For example, a clue like the character ( Rose, Ruth, Rita, Rene, Randi ) who had the tulip, her last name rhymes with the last name of the man who shot Abraham Lincoln would be a No No.

Another important meaning is that logic is required to make the puzzle interesting. Imagine a scenario with five kids. Bobby, Alica, Jan, and Terri. each finds a different number of easter eggs, from one to five. Clue one says that Bobby found twice as many eggs as Jan. In that case Bobby could have found either two or four eggs, with Jan finding one or two.

If another clue says that Jan was not the one to find one egg, we know Bobby found four eggs and Jan two.

Some redundancy in the clues is actually good as it allows readers to check themselves if using the grid, and also acts much like a red herring.

Once you've got your clues written Then comes the hard part. Writing the solution and logically proofreading the puzzle.

Some publications require that you give the solution from the completed grid. But it is a better idea to logically solve the puzzle in words. Basically, you resolve one problem after another until all are done.  FOR AN EXAMPLE SOLUTION PLEASE WAIT UNTIL YOU'VE READ PART II.

In your solution the references for clues that led to your conclusions are placed in parenthesis. In solution writing be as brief as you can possible be--just be concise. Usually when a conclusion is made it doesn't have to be repeated. Again check the format in the publication you are sending your puzzle to.

What I usually try to do is follow on clue to its conclusion and then work on the next one. If that is not possible, I simply resolve one clue at at time.

Once done with the solution you should write out the entire solution following the same pattern as your gird.

Then comes proof reading. It is not a bad idea to get a friend of spouse to check out your puzzle, by trying to solve it, and going over your solution. Remember, everyone makes typo's in writing--but if you have logical errors in your puzzle not only will you not sell the puzzle, but that publisher will probably never look at another puzzle of yours.

Before you send in our puzzle make sure your solution reference numbers match up with your clues.

If you like both logic writing and you can write logic puzzles and have fun while you bring in a steady income--while you write your mind boggling mystery.

Part II

Here is exactly how I do logic puzzles. I use software ( shareware ) which, if you like, you can try out and purchase if you find it helpful. However, you can use the same method without using the software. (The software just makes logically proofreading the puzzle almost foolproof--and the writing goes faster.)

I start a new page in my word processor or in the program. For this example I'll use a word processor

First I write the Scenario so that I know any definitions I need.  (REFERENCE) And give it as catchy a title as I can:

Packrat Trouble

When he arrived back at his mountain cabin, Fishy discovered the pack rats had been to work. In addition to making a mess of the entire cabin, five small items had vanished ( a gold pen, a key, his lucky dime, his pen knife, and his compass ). After hours of clean-up work he found each item in a different location ( under the bed, in the stove, in the trash, in a nest, and in the outhouse ) and at different times ranging from 9AM to 1PM. Can you determine which item was found in which place and at what time.

Next I do the solution table. Why do the table after the scenario? Just for convenience. I'll be referring to to the solution table as I write the clues so I want to be able to get back to it easily.

Item Location Time
Pen Knife Trash 9AM
Dime Nest 10AM
Pen Stove 11AM
Key Under Bed Noon
Compass Outhouse 1PM

( Back to "Just make a solution table " if you came from there )

I don't need a solution gird at this point because my computer program makes one up for me as I go along. However, if you not using the computer program you need to make up a solution gird for your puzzle so you can check off your clues on it. For this puzzle see PACKRAT SOLUTION GRID. (A big grid you can pare down for any size puzzle is provided at BIG  GRID ) Note the convention of labeling solution grids. If the labels across the top from left to right are Location, Time. Then the first name under Item going down would be the last label, i.e. the one on the far right of the top--Time. If there were more the order would be : last, the second to last, then third to last, etc.  SEE MONTANA GRID.

Then I start on my clues. I usually number them using the first number for the clue number and the second for the sentence in the clue.

//1.1 Fishy discovered an object hidden along with sticks, and mattress stuffing in the stove sometime before noon.

Set Stove Noon 0

Set Stove 1PM 0

The gird sample here is cut and the locations moved closer to the times to show how this is marked on a gird. grid image

The double slashes before my clue above tell my computer program to ignore the stuff that comes after it. Basically I just write the clue and then write down what the clue means in logical terms in a way the computer program can understand. Your solving grid PACKRAT GRID is simply a table of true and false facts. You fill in facts like whether Stove and Noon are true or false. If I were doing the gird by hand I would use 0's to mark false on the grid and an X to mark true. ( The computer uses 0's for false and 1's for true. ) Set Stove Noon 0 & Set Stove 1PM 0 is the same as setting Stove/Noon to 0 and Stove/1PM to 0 on your solution grid. Even if you don't use a computer to help proofread your puzzles you should still adopt a written convention like "Set Stove Noon 0" for your clues. It will help you double check your logic later. If you don't have a computer program to do it for you--you might want to print out and put these clues into the solution grid PACKRAT GRID as you go along.  

Just in case you haven't figured it out.  If all but one match in a column or row are set to false (0) then the last one has to be true (X).  If one is true all the rest are false.

//1.2 The shiny brass key was not the item hanging over the hole in the outhouse.

Set Key Outhouse 0

The key is not in the outhouse. Mark it on your grid.

//1.3 It was two hours after he found his lucky dime that Fishy found his key.

GreaterIsAdjacentToByX Key Dime 9AM 1PM 2

This is another computer term for a clue convention. The finding of the key and the dime are separated by 2 hours in time. Key is greater so it comes first, then Dime, then the range (AM to 1PM), then the number of hours.

We will know, if we find the time for the Key was found or the Dime was found, when the other was found. There are a few other things we can conclude from this and put into our solving grid. The computer program does this automatically. To do it by hand:

Key can't be 9AM or 10AM. Mark it on your grid.

Dime can't be 1PM or NOON. Mark it on your gird.

//1.4 Fishy didn't search the outhouse until after he ate lunch.

Set Outhouse 9AM 0

Set Outhouse 10AM 0

Set Outhouse 11AM 0

The Outhouse isn't 9AM, 10AM or 11AM.

//2.1 Neither the key nor the pen were found under a huge pile of tooth shredded paper in the trash.

//Set Key Trash 0

//Set Pen Trash 0

The Trash didn't hold the key and it didn't hold the Pen.

Notice the slashes here. These two Sets were "commented" out to see if they were necessary. I found, in fact, that I did not need these two clues to solve the puzzle.  See if you can reach the conclusion without these clues.

//2.2 Neither the compass or the knife were found in the huge nest made out of stuffing torn from Fishy's pillow.

//Set Compass Nest 0

//Set Knife Nest 0

Compass is not in the Nest and the Knife is not in the nest. These two aren't necessary clues either.

//2.3 Fishy found his lucky dime before he found his gold pen, but found it after he found his pen knife.

FirstIsGreaterThan Pen Dime 9AM 1PM

FirstIsGreaterThan Dime Knife 9AM 1PM

" FirstIsGreaterThan" is a lot like "GreaterIsAdjacentToByX " except that you don't know how far apart they are.

There are a number of things we can conclude here.

The Pen was not found at 9AM.

The Dime was not found at 1AM.

The Knife was not found at 1AM.

and because the dime wasn't found at 1AM and the knife had to be earlier

The Knife was not found at Noon.

See if you can figure out the rest. (This is why the computer program is so helpful. It just does all this for you. )

//2.4 Searching under the bed after 11AM,  fishy found one of his possessions.

//Set Bed 9AM 0

//Set Bed 10AM 0

//Set Bed 11AM 0

Again I discovered these clues were not necessary while working out the final written solution by hand.  Keep in mind, however, that there is nothing wrong with having more than one solution path, multiple solution paths just make the puzzle easier.  

//3.1 Fishy did not find his pen knife lying in the dust under his bed as if dropped for something else, nor did he find it in the spider ridden outhouse.

//Set Knife Bed 0

//Set Knife Outhouse 0

Also unnecessary.

//3.2 Fishy took an early lunch to celebrate his finding his pen at 11AM.

Set Pen 11AM 1

This one we find to be true. Set all the others on the same row and same column in the item/time group box to false.

//3.3 Fishy found his compass one hour after or one hour before he found his key.

//TheseTwoMustBeWithinXPlusOrMinus Compass Key 9AM 1PM 1

Again the puzzle can be solved without this clue. This time we know that either Key must follow Compass in the time line or vice versa.

//3.4 The search of the pack rat's nest took place later than the search of the trash, but before the search of stove.

FirstIsGreaterThan Nest Trash, 9AM 1PM

FirstIsGreaterThan Stove Nest 9AM 1PM

Same as above.

You are done when you can solve the puzzle using the clues that you written. All that is necessary then is to the put the clues together with the scenario as in SEE PACKRAT PUZZLE.

Part III

Once you have a puzzle with the clues worked out you need to write the solution. Here is how I do it.

I paste the actual solution table at the top for reference.

Item Location Time
Pen Knife Trash 9AM
Dime Nest 10AM
Pen Stove 11AM
Key Under Bed Noon
Compass Outhouse 1PM

For the Packrat puzzle I made up one table. A table with the times listed as my base.

Time Object Location
9AM

10AM

11AM

Noon

1PM

(You may need to make up more than one table, each with a different set of entries as the base for complex puzzles. Especially if you don't know which set of clues will best lead you to the answer. )

Another reason for listing the clues the way I did in Part II is that I can simply paste the clue into the solution where needed.

Start with something I am certain of. Note I move the reference number from the beginning to the end of the comment because this is the way the publishers like the solutions written.

Fishy Found his pen at 11AM (3.2).

Time Object Location
9AM

10AM

11AM Pen
Noon

1PM

Then build on it.

Fishy found his lucky dime before he found his gold pen, but found it after he found his pen knife. (2.3) So Pen Knife is 9AM and Dime 10AM.

Time Object Location
9AM Knife
10AM Dime
11AM Pen
Noon

1PM

Sometimes in writing solutions you need to set up something before adding it to the table. This was what I did in the next step.

Only remaining key and compass. Fishy didn't search the outhouse until after he ate lunch. (1.4) The shiny brass key was not the item hanging over the hole in the outhouse. (1.2) So compass is in outhouse.

I know the compass is in the outhouse but I won't use it yet.

Fishy discovered an object hidden along with sticks, and mattress stuffing in the stove sometime before noon. (1.1) The search of the pack rat's nest took place later than the search of the trash, but before the search of stove. (3.4 ) So Trash 9AM, Nest 10AM, Stove 11AM.

Time Object Location
9AM Knife Trash
10AM Dime Nest
11AM Pen Stove
Noon

1PM

Now we can use that fact that we established earlier that the compass was in the outhouse

It was two hours after he found his lucky dime that Fishy found his key( 1.3) Key was found at noon and was under bed (only remaining).

Time Object Location
9AM Knife Trash
10AM Dime Nest
11AM Pen Stove
Noon Key Under Bed
1PM Compass Outhouse

Compare the list with the list in our original table. It matches and we are done.

Item Location Time
Pen Knife Trash 9AM
Lucky Dime Nest 10AM
Gold Pen Stove 11AM
Key Under Bed Noon
Compass Outhouse 1PM

Lastly we write a summary of the findings. This should be set up to match our solution gird PACKRAT SOLUTION GRID ( first: variable from first group down, variable from first group across, variable from second group across,etc. )

Summary

Gold Pen, Stove, 11AM

Key, Under Bed, Noon

Lucky Dime, Nest, 10AM

Pen Knife, Trash, 9AM

Compass, Outhouse, 1PM

 

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Check out the logic puzzle software I use.

Other Sites of Interest

Logic Puzzles in General and Other Logic Puzzle Writing Advice