Science guy Bill Nye pulled no punches on creationism last week when he took to the stage to talk about science in schools.

On March 12, Nye delivered the keynote speech at the National Science Teachers Association’s national conference in Chicago, where he talked about “selfies, climate change, and (mostly) Creation Museum founder Ken Ham,” according to Education Week.

Apparently, he spent about 30 minutes of his two-hour talk on Ham, who he was in a public debate with about a year ago. Ham is a Christian fundamentalist who opened a Creation Museum in Kentucky.

Nye told event goers, “If you’re trying to indoctrinate children into an anti-science worldview, which is inane and silly, I ask myself whether or not you are acting in the best international interest,” and calling the museum “just another thing for people in the U.S. to have to apologize for.”

The other big focus of Nye’s speech? Climate change, what he called “the single greatest problem facing humankind.” Nye then did a signing for his most recent book, Undeniable: Evolution and the Science of Creation.

That’s our local guy, telling it like it is.