Mind-reading is one of the most popular effects used in mentalism performances.
And with the Book Test trick, it’s no different.
The goal is for the mentalist to call out specific words or a phrase from a random page in a book. When done correctly, it leaves the audience entertaining two thoughts:
1. The mentalist has memorized every single word written in the book; or,
2. The mentalist read the subject’s thoughts
Most audiences would lean towards the second conclusion, though either one is remarkably impressive.
Like all mentalist tricks, though, there is no supernatural feat involved at all.
So how is it done?
In this article, we’re going to explain to you how the mentalism book test is done. We’ll talk about the 2 methods and how to perfect them.
So let’s begin!
Method 1: Using a Hidden Bookmark
Of the 2 methods, this is the simpler and faster one. Aside from a book, the only other thing you need is a coin.
The Process
- Hold a book up to your subject, making sure the spine is against your palm.
- Manage your subject’s expectations. Tell him you’re going to rifle through the pages and he can say stop whenever you want.
- Once your subject tells you to stop, hold the book closer to him and ask him to read the first couple of words on the page.
- Remind your subject that he has to keep these words in mind.
- Go through the act of having him project his thoughts and slowly pretend to be able to tap into them.
- Tell them the first sentence on that page (and yes, it will be what he read).
Revealing the Trick
Choose the phrase and the statement. Before starting the trick, choose a page that you’ll use and remember the phrase that you’d want to guess later on.
Most mentalists opt for the first sentence, but you can change it up a bit by directing their attention to the bottom of the page instead.
The aim is to direct your subject’s attention to a sentence that’s easy to spot without giving away the fact that it’s a setup — so don’t say anything too specific, such as “Read the first statement of the fifth paragraph”.
Bookmark it. This method uses a coin as a bookmark. Once you’re determined which page and phrase you’ll use, insert a coin to mark it.
Working the book. This is where a bit of practice is required. When you rifle through the pages, do it lightly. Remember the speed of going through the pages becomes crucial. The goal is to stop at the page marked by the coin.
Don’t worry about whether the subject says stop earlier or later than your marked page. If this happens, rifle through the pages faster or slower the moment he begins to say stop. This makes the time difference between him saying it and you getting to the marked page without being noticed.
Once you’re at your marked page, have him read and remember it. Don’t make anyone spot the coin, though!
Close the book and set it aside. From this point forward, it’s all about the theatrics. As always, make it look like it’s taking a bit of an effort to read his thoughts before calling out the phrase.
Things to Watch Out For
If you’re choosing to go with this method, there are a couple of things you need to keep in mind.
Use the right coin. Make sure your coin is small enough to be hidden in the pages of the book. If it’s too big, your subject may notice it. Having a big coin may also make the marking obvious when you hold up the book.
Choose the right book. The thickness of the book matters in this method. Don’t use a book that’s too thin or too narrow. It’ll be harder to hide the coin between its pages and it leaves you less flexibility when it comes to your rifling speed.
Because of how this trick is done, using a hardbound book is discouraged. Paperbacks are always easier to handle.
Manage the movements. There are three moments when book handling is crucial.
The first is when you’re holding the book up just before you begin rifling it. Since the pages will be facing your subject, you have to hold the book about at least a fourth of the way in from its spine. It ensures that the coin stays in place without being seen.
Second, when rifling through the pages, do it from the middle. Rifling from the top or bottom corners of the book may not get you to the page that you want.
Third, when you ask your subject to read the phrase, make sure you are holding the book out to your subject. This lets them view the page, but also allows you to maintain control over how the coin is hidden.
Possible Variations
A nice variation is to write down the phrase. You can also turn it into a prediction by writing down the phrase on a piece of paper and making a show of hiding it somewhere at the beginning of your trick.
Method 2: Using Mathematical Equation
The second method uses a book and a calculator (or anything that will help your subject go through the calculation).
This is a method that doesn’t need you to be near your subject because once the book is chosen, the only person who’ll be handling it is him.
The Process
- Premise the act by telling your subject that you’ll be calling out a word or a phrase in a book, but that you won’t ask them to choose the page just yet.
- Introduce the idea of using a mathematical equation to randomize it and that he, the subject, has complete control over what number to start with.
- Set limitations — the number he chooses must have at least three digits, none of which are repeated. Say that this makes it more random.
- Once your subject has confirmed he’s chosen a number, hand them the calculator and begin.
- Have them reverse the digits of the number they’ve chosen. Then subtract the lower value from the higher one. For example, if they chose 472, reversing the digits would give them 274. They would then have to subtract 274 from 472. Their new number is 198.
- Once they have the difference, have them reverse the digits again and add this to their current number. Following the example from the previous step, they’ll have to add 891 (the reverse) to 198. They’ll get 1089.
- Tell them to separate the last digit — this is going to be the number of the word they’ll look for. All you need to do is find the page.
- If they have 3 digits left, that’s the page number. If they only have 2 digits left, tell them you’ll make it a little more random and have them stick a 0 between the first and the second. For example, if they end up with 72, it becomes 702 and that’s their page number.
- Tell them to look for the word that corresponds to the last digit that they set aside earlier. So if their last digit was 8, they look for the eighth word.
- Call out the word.
Revealing the Trick
Like other tricks that use mental mathematics, the calculations are designed to lead your subject to the same number every time. The magic number for this trick is 1089. It means when you’re setting up this trick, you need to memorize the 9th word on page 108.
Things to Watch Out For
Although most numbers will lead your subject to 1089 if they follow all the calculations, there are several that end up with 198. Examples of these are 475, 574, 576, and 676 — these bring your subject to 99 at step 5 instead of 198.
Since you’ve already said that they can choose ANY 3-digit number as long as they don’t have digits that repeat, putting limitations may make your subject suspicious.
Step 8 is a modification designed to address this. You’ll have to deliver it in such a way, though, that it looks natural.
Possible Variations
It’s best to begin with a single book, but you can eventually increase the number of books to enhance the illusion of free choice. It’s best, though, to limit it to three — this way, you just have to remember 3 words and make sure you match it with the right book.
In Conclusion
These are not the only ways to do the Mentalism Book Test trick — doing a little research online will open doors to other processes — but these two methods are good ways to begin.
As with all mentalism tricks, you’re going to have to put in the work to make sure you can pull it off. Even with the variation using the coin, there are still several things that could trip you up if you aren’t careful.
In the end, make sure to make it yours. Put in your own touches and make your patter uniquely yours.
Remember, although mentalists are encouraged to have a separate persona when they’re up on stage, it has to be something that’s connected to your real one.
So choose either of the Book Test trick methods and start practicing!