Sung-Min Park, 47, amateur cryptographer who has been decoding messages in public noise sources—radio static, CCTV footage, ambient city audio—since 2011. He has found no messages. He considers the absence of messages informative. He maintains detailed logs and submits occasional papers to cryptography conferences that are reviewed politely and not accepted. He distrusts GPS on the grounds that he cannot verify the signal source. He uses paper maps.

Isabelle Fontaine, 62, retired food critic who spent 30 years reviewing restaurants for two major publications. She never ate with colleagues on assignment. She considered eating alone the correct condition for assessment: no conversation to compete with flavor, no shared frame of reference to default to. She ate 12,000+ restaurant meals alone over her career. She now cooks at home and eats at the table with her husband and finds it harder than she expected.