Ricky teaches Karl some interesting facts about animals. Karl offers a misguided theory about evolution then recounts the latestscientific breakthroughs in medicine.
Karl addresses one of his pet peeves, animals who are treated like people, and issues a public safety announcement for chameleons.He considers the question, 'Does the brain control you or do you control the brain?"
Karl shares that he often goes on walks to observe ants, moths and other insects and that he once saw a bee have a heart attack.Karl asks if everything were the same size as humans, what would be the best animal to be.
Karl discovers he has a kidney stone and spends time in the hospital. Ricky stops by to visit and mock him. Karl considers animalsthat look like things and wonders if that's difficult for them.
Karl says he wouldn't mind life as a littler person, since everything from food portions to cities would be bigger for him. Stephenrecounts his night out at a London club.
Ricky reads some predictions for the future from an academic study, which leads Karl to share his theories. Stephen asks the guys iftoday were the end of the world, what would they do with their last day?
Karl contemplates how many different species are actually needed in the world, and whether or not we should keep looking for new forms of life. Karl questions if inventions like modern vacuum cleaners and toasters are necessary.
Karl reminisces about an overabundance of breath mints throughout his childhood. Karl dismisses cures for blindness found via research with mice. After years of nursing a childhood leg injury, Karl visits a massage therapist with dubious credentials.
After contemplating the concept of memory, Ricky and Karl role-play as the two lobes of Karl's brain. Karl describes a childhood weekend of talkative ghosts and befriending pocket calculators.
Ricky and Stephen challenge Karl to describe his ideal version of the world as conjured in a magical isolation tank, but Karl is suspicious of a perfect life. Karl describes his theory of the "Problem Hole."