A dictionary of Proverbs (Oxford Paperback Reference)

shirt see NEAR is my shirt, but nearer is my skin.
From SHIRTSLEEVES to shirtsleeves in three generations
Shirtsleeves denote the need to work hard for one’s living. This saying has been attributed to A. Carnegie (1835-1919), manufacturer and philanthropist, but is not found in his published writings. From CLOGS to clogs is only three generations expresses the same idea.

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  1907 N. M. BUTLER True & False Democracy ii. No artificial class distinctions can long prevail in a society like ours [in the US] of which it is truly said to be often but three generations ‘from shirt-sleeves to shirt-sleeves’. 1957 J. S. BRUNER in Psychological Review LXIV. 125 From shirtsleeves to shirtsleeves in three generations: we are back with the founding and founded content of the pre-Gestalt Gestalters. 1980 J. KRANTZ Princess Daisy xvii. What’s this? Shirtsleeves to shirtsleeves in three generations. ■ family; poverty
  

If the SHOE fits, wear it
A predominantly US variant of if the CAP fits, wear it.
□1773 New-York Gazette & Weekly Mercury 17 May Why should Mr. Vanderbeek apply a general comparison to himself? Let those whom the shoe fits wear it. 1876 W. G. NASH Century of Gossip 125 If the shoe fits you, you can wear it a little wile [sic], Jack; but we won’t quarrel about that. 1934 J. GREGORY Emerald Murder Trap 260 Some one, devilishly inspired, had made a noose in the end and the knot was what is so widely known as a Hangman’s knot. .. ‘There’s an old saying, you know; if the shoe fits, wear it. The words might be made to apply to knots, I suppose!’ 2001 Washington Post 13 Dec. C11 (Baby Blues comic strip) ‘Zee, you’re a know-it-all-crybaby-tattletale brat!’ ‘I’m telling Mommy that you said that!’.. ‘What did Mommy say?’ ‘She said, “If the shoe fits, wear it!”’ ■ conduct; reputation