It is well known that Book II of the Wealth of Nations (WON) insists on a passion common to all of us, the "desire to better our condition": a desire which, though generally calm and dispassionate, comes with us from the womb, and never leaves us till we go into the grave. This chapter describes focuses on the links between vanity and luxuries in Theory of Moral Sentiments (TMS), studying three chapters in which they play a prominent role. It describes the famous parable of the poor man's son. The chapter also discusses the usual interpretation, which explains the poor man's son behaviour by vanity only. It shows how the love of systems seems to create a bridge between TMS and WON, that is, between luxuries and capital. Satisfying vanity is undoubtedly for Smith the aim of the acquisition of luxuries. More precisely, vanity generates the distinction between luxuries and other goods (necessaries and conveniencies).