Through the varied experiences of Charlie’s caretakers, Pop explores the distinction between second-hand knowledge and direct experience. The novel contrasts Marcus’s outsider perspective with Chelsea’s firsthand knowledge of her father’s condition, demonstrating that true understanding comes only from direct experience.  

The reality of Charlie’s CTE comprises the clearest example of this theme, and the many reactions to the disease highlight the differences between casual understanding and experiential knowledge. As Charlie’s primary caregiver, Chelsea has more direct experience with Charlie’s condition than anyone else in his life. Watching her father slowly deteriorate means she’s seen him move through the stages of the disease, and this gives her a deeper knowledge of how to care for him and how much worse he will get. By contrast, Marcus learns what CTE is through online research. Though he comes to see many of Charlie’s behaviors as symptomatic, he doesn’t have the direct experience of seeing Charlie’s personality change over time. In Chapter 15 when Marcus explains Charlie’s CTE to McTavish, McTavish admits he’d read about the condition but just thought it meant people were “a little loopy from having their bells rung a few too many times” (140). Even Marcus’s limited experience with Charlie has increased his understanding of the disease, and he is now in a position to explain it to an adult whose understanding is much more limited. The value of experiential knowledge comes into play again during the journey to the induction ceremony, where McTavish at first thinks Charlie is doing well because he follows conversations about the past, but soon realizes the danger inherent in Charlie’s inability to comprehend the present. At the end of the book, Marcus and McTavish still don’t have Chelsea’s level of experiential understanding. However, Marcus and McTavish gain experience that helps them see Charlie’s condition from Chelsea’s perspective.

Charlie himself teaches Marcus about the value of direct experience. At the beginning of the book, Marcus fears the physical contact of football and avoids tackles whenever possible. With little experience of getting hit, Marcus’s fear prevents him from realizing his athletic potential. When he starts practicing with Charlie and taking heavy hits, Marcus’s experience helps him overcome his reservations because he realizes he can take a hit and get back up. This translates into a greater understanding of football offense, which allows Marcus to become a better, more well-rounded player. As a result, Marcus is less scared of taking or giving hits because experience has taught him that he can do so without serious injury. When Marcus blacks out in Chapter 24, the dizziness and nausea he feels upon waking challenges his new understanding of offensive play. Up until this point, Marcus has reveled in his new love of tackles because his experience has been positive. However, this negative experience forces Marcus to acknowledge that there are risks associated with how he chooses to play. Marcus’s decision to bench himself highlights how understanding changes with experience. Marcus realizes that he needs to look out for his own safety if he wants to play in the future. Though he is frustrated at taking himself out of the game, Marcus knows it’s the right thing to do. His knowledge of how tackles affected Charlie and his new direct experience with a concussion inform Marcus’s choice, showing how he learns both from his own experience and the experience of someone else.