1. Use the present tense “is” when (a) the person is still living or the entity still exists, and (2) the condition or situation described still subsists or persists up to the present time.
2. Use the past tense “was” when (a) the person is no longer living or the entity no longer exists, and/or (b) the condition or situation described no longer subsists or persists.
Examples:
“Baguio is the farthest I’ve ever gone.”
(The place is still there and you’re still around.)
“India was the farthest Alexander the Great had gone in his eastward conquests.”
(India is still around but Alexander the Great is long gone.)
***
“He is my first boyfriend.”
(The guy is around and he’s your first boyfriend. For your relationship’s sake, though, don’t make that statement in his presence; he might construe it to mean that you are thinking of having some other boyfriends in the future.)
“He was my first boyfriend.”
(The guy is still alive. He was your first boyfriend but no longer is.)
“He was my first boyfriend.”
(The guy is dead, regardless of whether or not he died when he was still your boyfriend.)
***
“Neil Armstrong is the first man to land on the moon.”
(His being the first man to land on the moon is a record that will remain for posterity, and he is living.)
**
“Jose Rizal is the greatest Filipino hero.”
(He is no longer living, but his being the greatest hero is a prevailing perception.)
“Jose Rizal was an oculist by profession.”
(He is no longer living, and his being an oculist no longer subsists.)
***
“Corazon Aquino was the first woman president of the Philippines.”
(Although her being the first woman president of the Philippines will always remain true, she is no longer living.)
“Corazon Aquino is the first woman president of the Philippines.”
(This was a correct statement when she was still living.)