time-travel-2
Explanation
The Joke
The comic depicts a conversation with God about time travel. Someone asks God why time travel isn't possible, and God explains they tried it once but it "breaks stuff." The person then asks the classic question: couldn't you go back in time and kill Hitler? God corrects them -- you could only kill "potential Hitler," since before his atrocities he was just a regular person, and asks if the person really wants to go around killing potential future dictators. They agree it's a gray area.
The person then suggests that with advanced technology, couldn't you just travel back and diplomatically convince potential Hitler not to become Hitler? God says "Sure" -- but then points out the catch: if time travel becomes possible, everyone will want to use it, so "everyone is traveling to the same time." The implication is that all of history's time travelers would pile up at the same point, creating chaos. The final panel has God admitting "Engineering universes is simpler than I imagined" and wishing they'd stuck with "pure math, or pottery, or apples" instead.
The Humor
The comic systematically dismantles every version of the "go back in time and kill Hitler" thought experiment, which is perhaps the most well-worn time travel hypothetical in all of pop culture. Each proposed solution creates a new, worse problem: you can't kill someone for crimes they haven't committed, diplomacy would work but then everyone would want to time travel to the same historical period, and the resulting crowding would be its own catastrophe. The final panel is a delightful meta-joke -- God as a universe designer expressing frustration that their creation has these annoying edge cases, like a software developer regretting design decisions. The mention of "apples" is likely a nod to the apple in the Garden of Eden or Newton's apple.
References
The "kill Hitler" time travel scenario is one of the most common thought experiments in discussions of time travel ethics and paradoxes, frequently referenced in science fiction and philosophy. The comic also plays with theological concepts by having God serve as the universe's engineer/designer, frustrated by the complexity of the system they created.