Is it correct to ask "How come?" when you mean "why?"?

Answer 1

It is perfectly fine informal use, and has a very long history. But note that it only substitutes for SOME uses of "why" not all. (Thus those who have mocked it here by substituting it for uses of "why" it is NOT equivalent too are totally missing the point.)

Background... exact meaning:

The expression is simply an abbreviated version (which became common in 19th American speech) of "How comes it that..? --which you will find in English writings going back at least to Shakespeare. The full form of the question in modern English would be something like "How did it come about that...?" or "How did it come to be...?"

The reason that people would say just "come" (as also in "How comes it?") instead of "come about" is that this is an older sense of the verb "come" that means "become, come to be". Nowadays if we wanted to use a fuller form we would be more likely to ask "How is it that?"

Actually, it was originally a more precise question than our word "why?" "Why" can be used to ask about the PURPOSE of something** (e.g., asking "Why did you say that?" to find out what someone hoped to accomplish by saying it) as well to inquire about the ORIGINS/CAUSE of something (e.g., "Why do we say it this way?" when we want an explanation of the HISTORY of an expression like "how come?") "How come(s it that)?" originally only referred to the origins

**An older way of specifically asking the purpose (or end), is "wherefore" (meaning 'for what [purpose]?') But, of course, we don't always make nice distinctions like this.

Answer 2

How come? is more spoken-english, "WHY" is the written equivalent.

Correct: We don't know why he ate uncooked meat.
Incorrect: We don't know how come he ate uncooked meat.

... Also ...

In spoken English both sentences "sound" ok, but in written, the second is the only stylistically correct option.

Awkward: How come Julia carries a blue purse?
Correct: Why does Julia carry a blue purse?

Answer 3

Noun 1. why - the cause or intention underlying an action or situation, especially in the phrase `the whys and wherefores'
wherefore
reason, ground - a rational motive for a belief or action; "the reason that war was declared"; "the grounds for their declaration"
Adv. 1. why - question word; what is the reason (`how come' is a nonstandard variant); "why are you here?"; "how come he got an ice cream cone but I didn't?"

Answer 4

I always used the two interchangeably - I don't think there is a difference, so I think it is correct. Kind of like saying perhaps instead of maybe - they both mean the same thing.

Answer 5

Sure, why not?

Sure how come not?

Answer 6

how come would you ask that??? : )

Answer 7

NOOOOOOOOOOOOOOOOOOooooooooooo