The episode argues that pure white is a convention rather than a fixed fact: screens and printer paper target CIE standard illuminant D65, the average color of noon daylight. People perceive white when light is distributed like a black body radiating at 5,800 to 6,800 kelvin, and sunlight seen from space is closest to sRGB FFF3EF, with a hint of red and green, before Rayleigh scattering in the atmosphere filters it. Strictly, shading white with black only makes gray, so shades of white really means off-whites that differ slightly in hue and chroma.

Color names follow the materials people handled: snow around 1000 AD, ivory in 1385, cream in 1590 and alabaster in Shakespeare’s The Rape of Lucrece in 1594, later joined by beige around 1887, seashell in 1926 and cornsilk in 1927. The 1987 X11 web colors locked these into hex codes, such as old lace at FDF5E6 and cornsilk at FFF8DC, and invented cool tones like ghost white, F8F8FF, to balance nature’s warm whites. Off-whites boomed from 1955 to 1975 and now dominate paint aisles because lighting changes how they look, while Crayola rebranded White Smoke as Cultured Pearl and released a scented Baby Powder crayon in 1994.

• Benjamin Moore offers 152 off-whites, Behr 167 and PPG 315.
• Beige comes from a French term for undyed natural cotton.
• Ghost white, floral white and antique white have no record as color names before the 1987 X11 list.
• Crayola’s Baby Powder, hex FEFEFA, has a yellow tint so it shows up on white paper.
• Even a mathematically perfect D65 wall reads as off-white under a warm lamp or at sunset.