"This is a fascinating work and a tool that supplies the reader with an abundant supply of new and usable material... Self-working effects, based on clever mathematical principles are often a relief to perform and give you ability to concentrate fully on your presentation. Parimental explores just one such principle with some 20 different effects to choose from along with some very sound presentational advice."
- From the Foreword by Richard Osterlind

Learn to control your participants' thoughts and predict their actions using the Parity Principle - an underrated, very simple principle published by Martin Gardner in Scientific American in 1960. This versatile principle can be used impromptu or for prepared routines. It can be adapted to use in any type of venue, including online performances.

The basic routine involves setting up a series of nine items in a three-by-three grid. The participant has a free choice of starting on any object. A number is freely chosen and the participant moves to the left, right, up or down, back and forth. The performer now shows a prediction that shows which objects the participant is not on, and they are removed. This continues until eight of the items are removed and the prediction reveals the item ended up on. These nine items can be anything you like and this book is filled with a variety of ideas to spark your creativity.

In this book, you will explore and learn the basics of the Parity Principle as well as many nuances that will allow you to make it even more versatile than ever. There are routines described which use celebrities, colors, business cards, playing cards, cities, typographic symbols, randomly selected objects, and more. There are also some essays on subjects that will help you more effectively perform these routines, as well as improve your performance of mentalism, in general.

It is a tool that you will use to create wondrous effects and it is an exploratory journey of an extraordinary principle that you will find amazing and unforgettable.

"Jheff did a superb job writing about and analyzing this beautiful principle. A must buy for all mentalism thinkers."
- Marc Salem

"Parimental will teach you a mentalism technique that you can use to construct powerful routines of your own. If you're not the creative type, then Jheff has done all the thinking for you, providing an array of solid presentations. If you are looking for foolproof predictions with kicker endings, you've found the source."
- Paul Brook

"So glad Jheff is releasing this book. Just BUY IT! You'll love it!"
- Looch

"It's so versatile and these are the effects we need. As a corporate performer, I'm always looking for routines that can be custom-made and this is one of those. This is a very good investment. Well done, my friend!"
- Luca Volpe