Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

This comic features a professor at a lectern delivering what appears to be an argument about the cruelty of life's timing. He observes that when you were 15, you could have eaten outrageous junk food like fried chicken with Oreo breading -- your body could handle it -- but your parents wouldn't make it for you. By the time you're an adult and can make it yourself, your body can no longer stomach it.

The caption reveals this is "Professor Westover explains why he's an atheist." The humor lies in the absurd mismatch between the gravity of atheism as a philosophical position and the trivially mundane evidence offered in its support. Rather than citing the problem of evil, the silence of God, or the lack of empirical evidence, the professor's case against God's existence rests entirely on the cruel cosmic irony of junk food timing -- you can never eat the most indulgent foods at the moment you'd most enjoy them. It is a playful riff on the "argument from evil," scaled down to the pettiest possible grievance.