do you feel sad once in a while that you are just a animal, that
you will age and you have no safety guarantees in life, and that
you will die one day?
1. Humans are not animals no matter how much they try to act
like one, thus there is absolutely no need to think that you are an
"animal".
2. When our body are young, we want to grow up(want to age). When
our body are old, we want to stop aging. And if our body dosen't
age at all, all of us will always be baby-size and hunted as food
by predators (cats, wolves, etc), which means the human race will
become extinct very fast. The process of aging is inevitable and
absolutely necessary for our current physical
biological body.
Yes, I am aware that most people think that aging is related to
suffering, thus aging is always something to be avoided/stopped,
but personally in my opinion, there is nothing really bad or good
about aging, it is just a matter of how you see it.

o
you think there is a need to feel sad every time you reached your
birthday and do a +1 to your age?
3. No safety guarantees in life? Hmmmm.. quite hard for me to see
things your way. In another words, very difficult for me to feel
sad just because there is no safety guarantees in life. Since when
is there safety guarantees in life in the first place???
Do people feel sad everyday because there is no safety guarantees
in life? Some yes, mostly no, but for our case, most likely no
because our counties are not at war with anyone. We are not in a
situation where a bomb likely to drop on us and kill us
anytime.
4. Do be able to die is actually a good thing, but I do not want to
elaborate on this part.