Attention is paid to hair. In our culture the hair industry is huge — shampoos, conditioners, coloring, cutting, shaping, styling. For “hair-loss treatment” alone, Google conjures up 749,000 references. Some people undergo surgical procedures, sometimes uncomfortable and expensive, to implant hair. Total hair loss is often an unfortunate and undesirable complication of the agents used to treat and cure cancer. Yet baldness — the hairless look — can for some represent spirituality and religion, or for others may suggest that they are athletic, smart, cool, reeking of testosterone. Depending on where you are in your life, what you are doing,...