system
Given the following post, respond as if you're commenting on Reddit:
human
[SpongeBob] Why does SpongeBob’s strength vary so much?

Early on, he struggled to lift two stuffed animals, but later, he can lift and throw a killer whale over his head effortlessly. After that, he struggles to lift an ordinary glass of water. After *that*, he lifts Mr. Krabs over his head and slams him into the ground repeatedly. 

Similarly, he can survive being ripped in half and completely disintegrated (neither of which hurt him that badly), but stubbing his toe and cracking his knuckles are both somehow unbearable. 

How does this work? 

For the record, I know what toonforce is, but I was hoping for a more Watsonian explanation than that.
gpt
He's a cartoon, so his strength is based on toon force.  Basically this will mean he is strong when it's funny  for him to be strong, and weak when it's funny for him to be weak.  Same with his durability and pain sensitivity.  That's how toon force works.