Fun to Imagine by Richard Feynman

I hate(d) physics. I hated it cuz I could never learn it.

That all changed when I watched Richard Feynman’s “Fun to Imagine” series from 1983.

It’s so good that I rank it #1 on my list of The 10 Best Richard Feynman Documentaries. And I also rank it #1 on my list of Best Physics Documentaries (out of 15!)

Feynman explains physics like Buffett and Munger explain business.

And he’s just so nerdy-cool about it.


Trailer for “Fun to Imagine”

The above clip is mediocre quality but it’s one of my favorite segments of the documentary. The links below to the full documentary are of higher quality.

Watch “Fun to Imagine”

This was originally shot on 16mm film at Feynman’s house in Altadena, California.

It was first broadcast on BBC2 in July 1983.

You can stream Feynman’s “Fun to Imagine” video for free on:


  • My Rating: 99/100
  • IMDB Rating: 9/10
  • Rotten Tomatoes Ratings: /100 (Users); /100 (Critics)

Review of “Fun to Imagine”

This doc is a collection of 8 or puzzles that Feynman explains each in Plain English.

Jiggling Atoms

Feynman explains that everything is made of atoms, which are constantly in motion. This motion is what we perceive as heat.

When atoms move faster, the substance is hotter; when they move slower, it is cooler.

He uses the example of a bouncing ball to illustrate how atoms transfer energy through collisions, explaining how heat spreads from one object to another by the jiggling of atoms.


Feynman describes fire as a chemical reaction where oxygen atoms in the air combine with carbon atoms in the wood. This process releases energy that was originally stored in the wood by the sun.

He likens the reaction to a ball rolling into a deep hole, where the atoms snap together when they get close enough, releasing energy in the form of heat and light.

Rubber Bands

Feynman discusses the elasticity of rubber bands, explaining that the stretching and contracting are due to the movement of molecules.

When a rubber band is stretched, the molecules are pulled into a more ordered state, and when released, they return to a more disordered state.

He also demonstrates that stretching a rubber band makes it warmer because the molecules move faster and generate heat.


Feynman explores the forces of magnetism, explaining how magnets can attract or repel each other without touching.

He delves into the concept of magnetic fields and how they interact with each other. He also touches on the difficulty of visualizing atomic behavior and the abstract nature of quantum mechanics.


Feynman explains the nature of electricity and electromagnetic effects. He discusses how electric currents flow and how they create magnetic fields.

He also explains the relationship between electricity and magnetism, which is fundamental to understanding how many modern technologies work.

Mirror and Train Puzzles (the mirror one is the hardest of all of these for me to understand!)

Feynman presents thought experiments involving mirrors and trains to illustrate interesting perceptual phenomena.

For example, he explains why mirrors appear to reverse left and right but not up and down, and he discusses the behavior of objects in motion relative to each other.

Seeing Things

Feynman explains the process of vision and how we perceive the world around us. It’s light interacting with our eyes and how our brain processes these signals to create the images we see.

He also touches on the limitations and peculiarities of human perception.

Big Numbers

Feynman discusses the concept of very large numbers and their significance in science.

He explains how understanding large numbers is crucial for grasping the scale of the universe and various scientific phenomena.

He uses examples to illustrate how large numbers can be both fascinating and challenging to comprehend.

Feynman’s Ways of Thinking

Throughout the doc, Feynman shares insights into scientific thinking and the imaginative process required to understand complex phenomena.

He emphasizes the importance of curiosity, creativity, and the joy of discovering how the world works. He also discusses the challenges and rewards of scientific inquiry.

I’m still not an expert in physics (or even in the evrerday examples he gives). But I find more joy in physics now.

I even tried teaching the coffee/jiggling atoms to my son!

Thanks for reading!

Rob Kelly, Chief Maniac, Daily Doc