Idioms and Proverbs

My friend asks this question:

 Q: Are ‘proverbs’ and ‘idioms’ the same or different? I heard “devil’s advocate” but I don’t understand what it means!

Can you please explain it to me and give me some examples? Many thanks!

  A: Thank you for your question!

Proverb = a well known saying that teaches truth.

Examples:

1. Early to bed and early to rise, makes a man healthy, wealthy and wise.
   Meaning: Go to bed early and get up early to have good health.
2. An apple a day, keeps the doctor away.
   Meaning: Eat healthy food and you will not get sick.

Idiom = a common saying that has a figurative meaning. That means that the words used are not literal. They have a different meaning.

Examples:

1. “I could eat a horse“: I am so hungry I could eat a horse.
   Meaning: I am VERY hungry.
2.  ”A bull in a China shop“: He does his work like a bull in a china shop.
   Meaning: Not careful. Here, ‘China shop’ means dishes and cups, not the country China. If a bull was in a dishes and cups shop, the bull would break everything!

Your Question: Devil’s advocate

“Devil’s advocate” means you will think about the negative side of the topic. Usually in English, we say “play devil’s advocate”

Example Conversation:

 A: I am going to ask Rebecca to marry me!

 B: Do you think she will say “yes”?

 A: Of course she will!

 B: Okay, but let me play devil’s advocate for a moment. What if she says “no”?  (Let’s think about the negative possibilities. What if she says “no”?)

 A: I will keep asking her until she says “yes”!!

Question: Is this an idiom, or a proverb?

 A: Where is the train station?

 B: I haven’t the foggiest.

What does “I haven’t the foggiest” mean?

Put your answer in the comments!