I Agree with Werther, but as it is there it means you have have your main goal as well as the smaller goal. Where as "You can't have your cake and eat it too." Means you can have one thing, but you can't have the other. Normally in reference to a larger goal at hand. For example: If you are in a race and you work really hard but only get second place. That's first earning your cake, but because you didn't get 1st place you don't get to eat the cake too. Or say you are on a mission to get bread and ice cream from the store, but you can only get bread because they are all out ice cream. Your goal was to get both but you could only get one. Soo that's having your cake but being unable to eat it. If you were able to achieve your goal and get both then that would be "having your cake and eating it too" Hope that was a good explanation. ^^

If you like Bob Dylan, there is a song called "Lay lady lay", that says exactly these words; here are the lines: Stay, lady, stay, stay with your man awhile Why wait any longer for the world to begin You can have your cake and eat it too Why wait any longer for the one you love When he’s standing in front of you Of course it is about the pleasure of a man and a woman being together, pleasure which which is renewed every time, so the cake never ends; in my opinion it is not one of Dylan's best songs, for instance you could compare with the mixture of feelings in another song, dealing with separation: title: "You are a big girl now", which for me is one of his best songs.

Usually this quote is written as: "You can't have your cake and eat it too ." Ria has explained both quotes perfectly.

Used for expressing the impossibility of having something both ways, if those two ways conflict, it's like this famous proverb : '' You cannot sell the cow and drink the milk'' choose only one thing, u can not have them both at once

but if you already ate it... can you have it?