What is "life"? What is "death"? Seriously, it seems like the basic questions are the most challenging. And everyone probably has slightly different responses to these questions. In reality, we probably don't know the one correct answer. But those simple questions bring up many other questions.
Are we our living cells? What happens when a cell (or all of our cells) stop living?
Are we our thoughts? Do our thoughts ever stop or remain stagnate?
Are we our "consciousness"? If so, what kind of consciousness? Subjective, objective, introspective, spiritual, phenomenal, access, etc.?
Are we the influence we have on others? If so, don't the ripples we make in the pond just continue to spread?
Are we our energy? Does our energy ever stop being transferred or converted?
Is there a "Heaven"? Where/what are the boundaries of Heaven and non-Heaven? What aspects of "us" goes "there"?
Is there "reincarnation"? If so, doesn't that mean we're going to be "here" longer? What aspects of "us" go "there"/"here"?
There are no right answers or easy responses. And these may even be the wrong questions! Until we penetrate "reality" more deeply, we are left with these grasps at the truth. So until further explanation, it seems that Thich Nhat Hanh has a good description of life and death that goes beyond life and death:
Sometimes people ask you: "When is your birthday?" But you might ask yourself a more interesting question: "Before that day which is called my birthday, where was I?"
Ask a cloud: "What is your date of birth? Before you were born, where were you?"
If you ask the cloud, "How old are you? Can you give me your date of birth?" you can listen deeply and you may hear a reply. You can imagine the cloud being born. Before being born it was the water on the ocean's surface. Or it was in the river and then it became vapor. It was also the sun because the sun makes the vapor. The wind is there too, helping the water to become a cloud. The cloud does not come from nothing; there has been only a change in form. It is not a birth of something out of nothing.
Sooner or later, the cloud will change into rain or snow or ice. If you look deeply into the rain, you can see the cloud. The cloud is not lost; it is transformed into rain, and the rain is transformed into grass and the grass into cows and then to milk and then into the ice cream you eat. Today if you eat an ice cream, give yourself time to look at the ice cream and say: "Hello, cloud! I recognize you."