Yes, it should be “how would I know?” in English, but a direct translation from proper Chinese 我怎么知道?, Singaporean Hokkien: “wa mana ei zai?” or Thai : “ja roo dai yung ngai” would be “how I know?”.
Like “how would I know?”, all the remarks above are often made in indignance or denial of responsibility. Sometimes, such denial is fair. For instance:
“How would I know you would come visit me if you didn’t call beforehand?”
“How would I know there is an appointment if you didn’t tell me?”
“How would I know you were standing behind the curtain?”
“How would I know you were sleeping under the car?”
When you do things or make plans that others cannot reasonably expect to do or plan, “how would I know?” is a reasonable response from them when something undesirable or disastrous happens.
But there are also instances where “how would I know?” is unreasonable. There are too many of such examples in my daily activities and encounters. Indeed “wa mana ei zai” is not a good excuse when such things are common knowledge. Of course, we can’t know everything; not even if it’s common knowledge. When these gaps are identified, the best thing we can do is to acknowledge our lack of knowledge, learn it, remember it and move on.
Of course, issues concerning “face” and “ego” affect everyone. We all feel good when our egos are stroked. We all feel unpleasant when we are embarrassed. Such feelings are universal. Not so universal, however, is the typical response from people whose egos are bruised. In some societies, including certain levels of our own society, shocking violence may greet a person who has not show respect for someone’s “face” or “ego”. Identifying and bringing someone’s mistake or shortcoming to light is sometimes viewed as an unforgivable sin. Simply criticising someone or forcing him to admit a mistake can result in extreme violence.
When dealing with these individuals, it would be wise to just walk away when they say “how I know?” when their mistake has been pointed out. Pursuing further for an apology may result in the scene above.
On a milder yet no less extreme and unreasonable note, there are cases where the ignorant control freak decides and dictates what everyone can do or can’t do and then turns around to shirk all responsibility when it turns out that their decisions have not been that good.
“This is your plan. Your idea. Look what’s happened.”
“How I know?”
“You insisted on this and that, threatening when it’s not done according to your wishes. Look what has happened?”
“How I know?”
Huh? Shouldn’t you be listening to others and not throw tantrums at people who may know better because they have been in the business for decades?
“How I know?”
Push it at your own risk.