Do gentlemen wear shorts? What are the rules regarding interior decor in a high-security prison? Is it ever acceptable to send Valentines cards to ones pets?

The twenty-first century is an age of innumerable social conundrums. Around every corner lies a potential faux pas waiting to happen. But if youve ever struggled for the right response to an unwelcome gift or floundered for conversation at the dinner party from hell, fear not: help is at hand.

In Rules for Modern Life, Sir David Tang, resident agony uncle at the Financial Times, delivers a satirical masterclass in navigating the social...