The 12 Levers: The Complete Psychological Toolkit For Improving Your Life

Spencer Greenberg · Jeremy Stevenson

Jul 2026 · Hachette Audio · Narrated by Evan Sibley

About this audiobook

The world of self-help is overflowing with advice. Countless books, podcasts, therapies, and videos talk about how to build a better life.. For Spencer Greenberg and Jeremy Stevenson, the most essential part of all this advice is the techniques. Techniques answer the million-dollar question: What do you actually do to fix your problem? What do you do to overcome anxiety, maximize productivity, and find inner peace?
After years of research—analyzing 106 self-help books and 23 therapies—they discovered that, from a bird’s-eye view, all self-help techniques collapse into just 12 broad strategies: The 12 Levers.
Knowing these Levers can prepare you for so many of the challenges that life will throw at you. You’ll learn how to…

• Clarify your intrinsic values to give your life direction
• Overcome fear by using the most scientifically validated anxiety approach in the world
• Alleviate insomnia and out-of-sync sleep routines with techniques largely known only to sleep therapists 
• Enrich your downtime by doing more glad-you-did-it activities
• Get more done by understanding the three factors of The Productivity Equation
• Interrupt spirals of self-consciousness using the Attention Training Technique

 
…and much more.
Together, the 12 Levers form the complete psychological toolkit for improving your life.

About the author

Spencer Greenberg is an entrepreneur and mathematician with a specialization in psychology. He’s the founder and CEO of Spark Wave, a psychology research organization that designs and conducts novel experiments and studies in psychology, and builds psychology related products designed to help solve problems in the world (e.g. scalable care for mental health challenges, and technology for accelerating and improving social science research). Spencer is also the host of the Clearer Thinking podcast, which is in the top 1% of podcasts globally. Through it, Spencer has interviewed many self-help figures and prominent non-fiction authors such as Scott Barry Kaufman, Loch Kelly, Kristin Neff, AJ Jacobs, Oliver Burkeman and Nobel prize winner Daniel Kahneman. Previously, Spencer co-founded AskAMathematician.com, a mathematics question and answer site which had about 50,000 monthly page views. He also founded ClearerThinking.org, which offers over 75 self-improvement tools and training programs used by hundreds of thousands of people, which are designed to help you improve decision-making, increase positive behaviors, and reduce cognitive biases.

Spencer has a PhD in applied math from NYU, with a specialty in machine learning. Spencer’s work has been featured by numerous major media outlets, such as Forbes, The New York Times, the Wall Street Journal, the Independent, Lifehacker, Gizmodo, Fast Company, and the Financial Times. Spencer also has extensive public speaking experience having done multiple talks including two TEDx talks here and here.

Jeremy Stevenson has a PhD from Flinders University and has published in academic journals (e.g., here, here, here, here), as well as outside of academia here. In addition to print publications, he has also appeared on various media platforms like radio and newspaper discussing his research. As well as a researcher, Jeremy is a clinical psychologist and has accrued thousands of hours of experience across hundreds of clients. He has studied self-help techniques both inside and out. He’s received dozens of therapy hours himself and attributes some fundamental transformations to this experience with excellent therapists.
 
When he completed his PhD he took a year off to study mindfulness meditation intensively - sitting month long retreats in Australia and Malaysia before doing a three-month retreat in Nepal. He’s tried every single one of the major self-help approaches in our list, including an experience of imagery rescripting that permanently increased his self-compassion, as well as a self-transcendent experience on a meditation retreat that has dramatically reduced his suffering years later. Jeremy also has extensive public speaking experience - he once did a job in his early 20s selling volunteer travel packages at North American universities that involved racing around doing dramatic announcements to packed auditoriums as well as full days of information sessions. During his PhD he won Flinders University’s People’s Choice Award for the 3-Minute Thesis in 2015, a competition in which you present your thesis to a lay audience. Jeremy works with Spencer at Spark Wave. You can listen to Jeremy on Spencer’s podcast discussing meditation here.