We're all made of star stuff

The title is a quote from the great Carl Sagan, but what he says follows closely with the Buddhist view of the universe.  Take for example, a rainbow.  You see a rainbow, and are amazed at its existence, but then a few moments later, its gone.  Did the rainbow truly exist at all, did it die?  Where do things go when they seemingly cease to exist?

The truth is one one of the 4 Noble Truths, that all things are impermanent.  This impermanence leads to suffering, as the ignorance in our mind distinguishes one thing from another as separate and not inter-dependent on each other.  This Noble truth also states that all things are without substance, to say that everything isn't by itself something whole, but all made of parts.  These parts are known as 'Aggregates'.  The rainbow isn't a rainbow as itself, but a collection of aggregates:  Water, Air, Sunlight.  Given the right conditions, these 3 aggregates create a rainbow for all to enjoy.  The water vapor eventually moves out of alignment, and moves on to water the plant life below, the sunlight eventually fades with the night sky, and the air moves on to let creatures breathe below.  The rainbow is not gone, but merely transformed into something else as its aggregates move on, never ending.  Human life is much the same way, we are all made of 5 aggregates:

1.  Form
2.  Sensation
3.  Perception
4.  Mental Formation
5.  Consciousness

The first is the most obvious of the 5, Form.  It's the odds and ends that make up our physical body.  Specifically, 65% Oxygen, 18% Carbon, 10% Hydrogen, 3% Nitrogen, 1.5% Calcium, 1% Phosphorus, etc etc..., the organs, the bones, nerves, the brain and everything in between.  When we're born we start to grow to adult hood, and when we reach that, we start to grow old and eventually die.  The cycle of birth, death, and rebirth known as Samsara.  When someone dies, their physical body doesn't just disappear, it decays and gives back to the soil its buried in, becoming a part of the tree, the plants, etc.  Just as the rainbow didn't truly disappear, so does a person physically, it simply changes Form.  The body also includes how we experience the outside world, mainly the 5 sense organs of the eye, the nose, the ear, the tongue and touch sensations.  Now this being said, in Buddha's time, little was known about biology and the fact that taste is also mostly a function of the olfactory senses and not the tongue, the distinguishing element is irrelevant as taste is usually in the mind different than smelling something.  The form is required to bring in the 5 senses of sight, smell, sound, taste and touch sensation.

Then we move to the more difficult to understand aggregates, Sensation.  When you sense a sight, a smell, etc, you can have the possibility of 3 results.  A feeling of Pleasure, a feeling of dis-pleasure, or a feeling of indifference.  These feelings on their own don't hold any substance without the sense organs that created them,  or the next step where these senses are processed into conceptualization known as perception.

Perception is where you take this sensation and make a conceptual reasoning with the feeling you receive from your sensation, and delegate a purpose, or a concept of what it is.  This is where you would realize you see, for example, a soccer ball.  You smell a rose, or you feel the soft skin of a peach.  This stage is strictly conceptualization, merely putting the dots together to form a hypothesis of what exactly you are experiencing.

After perception is when you reach a conditioned response to the stimuli, where you begin to take past experience and associate it to this perception and create a Mental Formation.  An example of this step could be that when you feel the peach, you remember that you like or dislike peaches, based purely on your past memory of pleasurable or non-pleasurable experiences with peaches, but only on a subconscious level.  You don't quite understand WHY you like or dislike the peach, you just have an instant reaction to it, which requires no thought, just an automated response.  To make more clear, Sensation has a direct emotional dimension, Perception has a conceptual dimension, while Mental Formation has a moral dimension, requiring data from more than the current moment.

Finally, we have Consciousness.  This is the aggregate of the mind that is most commonly understood by people, our conscious mind.  But even our conscious mind is merely a set of aggregates meshed together and 'appear' to be one single collection, but in fact its merely a set of aggregates within itself:

1. eye consciousness
2. ear consciousness
3. nose consciousness
4. tongue consciousness
5. body consciousness
6. mind consciousness

The first 5 are merely extensions of the aggregates of Sensation, Perception and Mental Formation of external objects, being anything we can perceive in the physical world.  You remember what you saw last year, you enjoy the sound of the music on the radio because you like the song.  You enjoy Mexican food because you have it all the time.  Rational conclusions that you are unaware are based in quite irrational mediums down the line of the sensory aggregates, perhaps effected by seeds you've planted in your mind this life, or countless lifetimes before.

The 6th consciousness, of the mind, is a bit more tricky to understand.  It is able to come up with concepts without external objects, these are known as thoughts or ideas.  Without the Mind Consciousness, the other 5 aggregate consciousness's could never interact with each other, as the mind consciousness is the coordinator of all 6.

The point of understanding all of these aggregates, is to realize that in the end, if you take away everything that can be deduced or proven as merely an aggregate of other parts, a person becomes nothing once everything is stripped away.  There is no soul that lives on, so to speak, when someone passes away.  They merely become of a form of something else, and with enough wisdom and insight, you can lift the ignorance from your mind and realize the truth of this.