What is it about sniffing that is so off-putting? Maybe because we have all sniffed at one time, or maybe because we have as children all been reprimanded and told to stop. I find sniffing deplorable, unmannerly, and anti-social. The woman next to me is an adult, foreign, she talks to herself, and she sniffs. Somehow, I find I cannot turn to her and criticise her behaviour. Of her many flaws I should tell her sniffing is the most intolerable. Saying that, the persistent whispering to herself as she scrolls through her phone pretending to ignore me ranks highly too.