It is often believed that the nude self-portrait is "perhaps the most intimate form of photography" (see, Preface to Self-exposure: the male nude self portrait by Reed Massengill
[link]. But, of course, every form of photography is intimate, "like good literature, readers see into another's soul, feel another's feeling, and experience a moment in the life of another person". (see, Portrait of a People, Customer Review
[link]