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On this week's Cosmos: A Spacetime Odyssey, Neil deGrasse Tyson taught us to see sound. Called "Hiding in the Light," the episode is structured around a bit of a play on words. For one thing, Tyson takes us through the scientific achievements that allowed us to understand the spectral code of light — a foundational necessity for modern astrophysics. But woven in that story is a companion tale about the nature of genius and, well, enlightenment. "Science needs the light of free expression to flourish," Tyson says at one point, as he outlines just how close we came to missing out on a pivotal discovery that changed the course of scientific inquiry. 

Rhapsody in blue

Danielle: When we discussed the first episode of Cosmos, I mentioned that Tyson said in an interview that the show aspired to capture the interest of people “who know they don’t like science.” At the time, that seemed like polite code for “Christians,” considering how much time episode one -- and two, and three, and four -- devoted to carefully and systematically crushing creationism as a rational belief. But in episode five it seemed that Tyson was trying to win over a different type of non-science personality -- the liberal-artist. Though, again, the episode was super dense, it was also bolstered by classical music and it was aesthetically intricate. Tyson told us about the first camera, how color works and why it’s important, and what music would look like if we could see it. All very technical, complex stuff that is still really pleasing on a creative level.

Abby: It makes a lot of sense for Cosmos to juxtapose creative expression and the technical achievements that help us understand it, because Tyson was very much trying to make a point about "genius" in this episode. How did we come to really "see" light, beyond the immediately visible? Somebody tried something new. "The nature of scientific genius is to question what the rest of us take for granted, then do the experiment," Tyson says at one point. In an episode about the scientific method, Cosmos is emphasizing the necessity of the extraordinary. And, arguably, in the necessity of nurturing it. The story of Joseph von Fraunhofer simultaneously demonstrates how one extraordinary experiment can change how we see the world, and how close we came to never having that act at all. "We never know where the next genius will come from," Tyson says of Fraunhofer's early death, probably from complications from his laborer childhood, "How many of them do we leave in the rubble?"

Danielle: I loved the nod to the scientific method in this episode, and though I agree Tyson stressed the majesty of genius here, he also showed how democratic scientific achievement can be. The infrared scene was especially elegant -- Tyson shows that Fraunhoser, an exquisite thinker, relied on mandated experimental controls to make his discovery. If you are thoughtful and careful and you follow the method, you could make a significant breakthrough -- just like Fraunhofer.

Abby: There's a really interesting historical connection mentioned in this episode that I missed the first time around: The Abbey at which Fraunhofer made his greatest discovery is the same place where the Carmina Burana were written. The Carmina, a set of 11th century poems written by monks, were later set to music by German composer Carl Orff. We heard an organ rendition of the famous "O Fortuna" movement from that composition during the visible sound waves scene. 

Speaking of history, I was relieved that episode 5 finally got around to discussing the substantial scientific contributions of non-western philosophers and scientists. Although, as we learned, a lot of early non-western achievement in China was halted by the formation of the Chinese nation, China basically invented everything before the West did. And the Islamic scholarly tradition saved a ton of the historic record while the West was in the dark ages. 

Danielle: Yes, and I think it was odd that that there was so much general negativity in the scenes about Mo Tze. There seemed to be a heavy anti-state message that functions as a stand in for the anti-organized religion stuff we saw in earlier episodes. "Science needs the light of free expression in order to flourish,” says Tyson, which calls back to the focus on artistry and creativity. Throughout the series we've seen a focus on individuality -- Isaac Newton, Bruno, William Herschel and others are given full, familial back stories, and we see their scientific triumphs through the lens of their personal development. It's extremely tidy, but the shared moral — fight the man, basically — lacks some nuance. 

Abby: You know, I'm still really conflicted about their approach to history of science on this show. As we've discussed before, the show seems to want to use these stories as parables. They're condensed, streamlined, and imbued with a lesson. As a storytelling device, I think it's effective, and I'm enjoying the animated segments used to reenact that history. But these parables must be a big ask for the portion of Cosmos's audience who know the actual historical record. I think these parables work best when Tyson tells them personally. For instance, in this episode the audience is guided into the importance of Fraunhofer's discovery through Tyson's kind of emotional fanboyish reaction to it. That enthusiasm makes it easier to digest the somewhat complex scientific explanation behind why the Fraunhofer lines are so pivotal. 

Danielle: Yes, when Tyson gets excited it seems about things it seems like more of a jumping-off point for the viewer than a sealed package of information. Watching Tyson peek into the lives of his heroes makes me want to learn more about them, whereas when the stories are contained it's easier for me to zone out. I wonder if these vignettes are an attempt to appeal to non-science nerds, those watchers who are on the verge of flipping to a documentary on U.S. history but may be pulled back by a story that highlights individuals over equations. This could entice a broader audience but, like you said, would irritate more informed viewers. 

Abby: Not to jump ahead too much, but my favorite tweet of the night was the following: "Ten-year-old me is super jealous of the millions of kids who now get to watch on substitute teacher days." Although for me and my nostalgia, the original Sagan Cosmos is still the ultimate substitute teacher day show, this episode really underlines that Tyson is owning the inspirational mission in his reboot. 

Danielle: Definitely. And I think he's picking up steam as the series progresses. Tyson again reminded us that we are all made of star stuff at the end of this episode — this time to much greater effect, which is interesting because (aside from the discussion of the spectrum) this week's show didn’t have much to do with outer space. It was all sound waves and light waves last night. But still, the episode did such a good job of drawing connections where there appear to be none — between atoms and color, sound and speed — that the notion of things being fundamentally, atomically connected was implied, and the star stuff line emotionally effective.

But what did the Internet think?

Abby: Especially considering that Cosmos was up against the Game of Thrones premiere this week, the Twitter response to the show still seemed to remain pretty strong. 

A few people picked up on what amounted to a big inside joke for the fans of the original Sagan series: Tyson said the words "billions and billions" in his narration. It's a phrase famously attributed to Sagan, although the late scientist denied using it (he later used it for the title of a memoir). 

Although anti-Cosmos tweeting was pretty muted this week, some noted a few tidbits from the episode that are sure to expand the show's hate viewership beyond young earth creationists. Hint: it has to do with Tyson's (accurate) assessment that the Islamic tradition saved a large portion of the Western historical record, and made significant contributions of its own to astronomy. 

Meanwhile, the official Cosmos account used some emojis: 

What we learned

Danielle: This episode was full of stuff I didn't know — starting with the fact that the names of so many areas in math and science, like algebra, alchemy, algorithm and even alcohol, have Arabic roots, and I didn't know anything about either Mo Tze or Ibn al-Haytham. I also didn't really know Tyson could raise his voice, which he sort of did when he got excited about light during the forest scene. That was weird. 

Abby: While I know that I learned a little about Fraunhofer and his eponymous lines in school, I have to say that I'd forgotten most of the details. And I certainly had no sense of the discovery's implications for the future of our understanding of the universe, or how perilously close we came to never having Fraunhofer at all. 

Check out our discussions of previous Cosmos episodes below: 

Episode one: What Does Neil deGrasse Tyson's Cosmos Say About Religion?

Episode two: Neil deGrasse Tyson Addresses Creationists' Evolution Fears in Cosmos

Episode three: Neil deGrasse Tyson Makes Us Feel Inadequate on This Week’s Cosmos

Episode four: Neil deGrasse Tyson Says Time Travel Is All Around Us on This Week’s Cosmos

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