A well known phrase

[hiflier]

What is the origin of the saying, 'to know something like the back of your own hand'?

[Quizmonster]

It's really a sort of proverb. To be honest, I've never understood it. I'm far from convinced that - it I were shown a set of photographs of various hand-backs including my own - I'd be able to pick mine out! I'm assuming that they were all 'normal' and not marked in any particular way.

[hiflier]

It's just as I thought. There does not seem to be an answer to this question. I've looked in all the 'phrase and saying' books to no avail. Even Arthur C Clarke didn't know, see his third sequel to 2001 Space Odyssey. But I am convinced that it comes from a card game, probably poker. With cards down on the table, only the player knows what's 'on the back of his own hand'. Anyone got a better idea?

[Quizmonster]

I'm not convinced by that idea, Hiflier. Surely if you lay your cards face-down on the poker-table, it's the back of your hand you're looking at! It should look exactly the same as all the other players' laid-down hands.

I'm sure it's simpler than that and just means - given that, as we work etc, the backs of our actual hands are constantly visible - that we ought to remember exactly what they look like.
For a cook, typist, carpenter, computer-user, masseur or whatever, their hands are constantly within their peripheral vision. As a result, over the years, one might expect that they would become familiar with what they look like.

However, as outlined in my earlier answer, I'm far from convinced that actually happens. It sounds like a no-brainer but really isn't, in other words.

[hiflier]

I do take your point, quizmonster. However, with the cards face down it is the 'back' of the hand that is invisible and known only to the player, the 'front' being what the rest of the world sees. If this is not the explanation, then there has to be something better than the notion that we can recognise our own hands!

[Quizmonster]

The earliest recorded use of the phrase is from 1943, in Wall of Eyes by M Millar, according to The Oxford English Dictionary. He/she wrote, "I know him as well as I know the back of my hand."
Given that we have been playing cards for centuries, I think 1943 is rather late for an explanation related to a card-game. (The game of poker itself is first mentioned in the 1830s.)

The phrase is younger than I am! But, what the hey! You're welcome to your own interpretation. I'll leave it at that.