Mark Rober walks onto a TED stage, detonates a bottle of liquid nitrogen, and argues that science class is broken—then announces he's spent two and a half years fixing it.

Neil deGrasse Tyson shows us the gradient — 90% to 60% to 40% to 7% to zero. The HHGTG universe got a clean break when the Babel fish eliminated God in an afternoon. We got a slope. Loki, who is ghost-writing the God Books, has thoughts about which is worse.

In which Loki confesses to engineering the cannabis normalization crisis in American high schools, explains the elegant logic of pre-sedating a generation, and is forced to admit the plan has a biochemical complication it did not anticipate.