How we know or that we know?

“Is it important how I know or that I know?”

I was watching an episode of Suits, which happens to be my favourite show these days and at one point, Donna, the secretary of a Closer discovers that the associate he has hired did not actually go to Harvard Graduate school and when she says so in casual conversation, he anxiously asks, “How do you know?” to which she responds, “Is it important how I know or that I know?” That got me thinking on a larger scale about whether it actually is important where the knowledge came from or that the person has acquired it. Personally when people state something, I instinctively ask, "how do you know? where did that come from?" It's just something we do. However, I think there are various kinds of knowledge where the source is important and others where it just isn't. In math or natural sciences or anything that requires a definite answer, it is extremely important to question it and find out who said it, whereas in areas of knowledge such as the arts or ethics, there are some things where people do not know how it is known, but rather just accepted anyway. A literary piece about imaginative concepts is not going to be asked how the writer knows what they have written, but a thesis would be. Similarly with ethics no one can answer how they know a certain deed is morally wrong, it just is based on its regard in society and on a conscientious level. It also depends on the pragmatism of the proposition of knowledge, if it is something that does not have a lot of value then it will not be scrutinized much whereas something that holds a lot of importance would constantly be.