Mark was/is the founder of Facebook?
If Mark is going to an Invester (when Facebook was just made by him), then how would he introduce himself?
Sir, I am Mark. I am/was the founder of Facebook.
I am confused about the usage of was/is for something that is still true. Here is another example:
My father was/is the architect of this house.
Which one should I use?
Assuming (as it is) that Mark was and still is the founder of Facebook, then both are correct. It makes more sense to use the present tense, since it conveys the extra information that both Mark and Facebook are still around.
If you say "My father was the architect of this house" (as opposed to "is"), I would be inclined to think that your father has passed away.
If a person says "I was the founder of company X" (in the first person), then knowing the person is alive I would be inclined to think that company X doesn't exist anymore.
