In any given philosophy the effort of logic is used to think rationally about why we feel the way about things we do. I can give you the textbook reasons for why history, and by association our ancestors, are important. But can I give you the feeling of why the are important, or even should be important emotionally? Not easily, no.
For most of us we look to the present and the future. The dead can do nothing for us. They cannot lift a hammer, they cannot provide words of comfort, they cannot tickle us or laugh at our jokes or lift our spirits as we struggle to live our lives. So for most of us we simply miss them and what they did for us once upon a time. We recall some small words of wisdom and wonder trivially at their lives. And then we forget them until maudlin melancholy once more jumps us late at night or on a lonely afternoon.
But the dead do so much more for us constantly, and consistently.
Each stone I cleaned I realized that an actual person was buried here. Someone who lived, like I am doing now (and will hopefully be doing far into the future.) By recognizing, honoring and justifying their life, I am doing the same for my own. I realized that what the chinese do is just the opposite of "cogito ergo sum." I think there fore I am is not true at all, in fact it is a little selfish and isolating.
I would rather say "To remember you, I must be." If that makes me more real then so be it, but most importantly it makes you real too, and consequently the world is a little less lonely and a little less overwhelming.
Yu Ling, an intern at the museum once told me that his grandfather inspired him to go to america to learn about history and culture. I later learned his grandfather was dead well before he was born, but that he talked to him regularly. I never really understood why anyone would do that. I accepted it, but did not understand it. Now I think I do, just a little bit.