the intentional taking of one's own life.
for most people the thought of suicide is tragic. why? because we are taught from birth that we mean something. that we are important. we are taught to cling to everything "for dear life" as the idiom goes.
now interestingly, somethings are ok to cling to, others are not, but we cling to both regardless as if it somehow matters.
the bad? materialism, obviously the biggest one. any one of the seven deadly sins: wrath, greed, sloth, pride, lust, envy, and gluttony. all of these are essentially, at their core, grasping for things we don't need to the detriment of ourselves and those around us.
and the good? life (ours and others) is ok to cling to. love is acceptable. your government would lead you to believe you are required to rely on them. as if they didn't exist neither would your safety. which is another good one. who doesn't think being safe is worth it, at almost any cost? even at the cost of other's happiness in most cases. safety is a delusion to itself, which perhaps warrants further discussion later however for now think of it in terms of national security, as that is something we can all identify with. the patriot act. gay marriage. you get the picture.
ok. so. here's where it gets weird for the uninitiated. if i start to lose you, bear with it. this is something that you may not agree with at first. but if remember this (which is another topic that deserves full disclosure that we won't get to here): if you only ever accept what you believe in as the truth, you never have a chance of enlightenment. and that, ultimately, is what i understand the purpose of zen buddhism to be.
now. what if i were to tell you that nothing is worth clinging to? not even the good stuff. suicide is the only answer. not suicide of the physical body - though that i wouldn't necessarily consider bad either - but here we are talking about suicide of the idea of the self. the ego. intentional ego death at the hand of the only one who can kill it. you. there is no other way to enlightenment, or as i see it - unconditional compassion for all things, alive and not-alive.
perhaps you're thinking this is impossible. because after all, you have a soul. don't you? or do you? or maybe you have your doubts about the soul thing, but you believe in your physical self. you see and hear and have friends and family and you love them. certainly then, love must be proof that you exist. proof that you have a purpose. because everyone loves. i'm not going to argue that almost everyone loves and has the need to feel loved. that's true. it is a large part of the human condition. but your existence doesn't depend on it. you can take away love and you will still exist.
but you don't want to give up love, do you? it's scary. and we love to love! i am no exception. love is wonderful. but it is far from everything as you will learn first-hand. when you step back and look at the whole picture of life, it is but a small part.
i think the most important concept to understand here is that love as you know expands beyond those people and things that you want to love - but everything, everywhere, throughout all of space and time.