Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

This comic explores a moment of existential crisis triggered by an innocent interaction. A wife asks her husband to bring their daughter Susie an apple juice popsicle because she is feeling sad. When he goes to comfort her, Susie asks a surprisingly profound question: "Once we understand how reality works, what are the odds that it'll be something humans find satisfying?"

The father is shown in a silent panel, stunned by the depth of the question. In the final panel, he is sitting alone outside at night, eating the popsicle himself, clearly shaken by his daughter's inadvertent philosophical insight. The joke is that the child's question -- essentially asking whether the fundamental nature of the universe will turn out to be compatible with human happiness -- is so devastatingly on point that the father is the one who now needs comforting. It plays on the trope of children saying unexpectedly profound things that leave adults in existential despair.