I have always paid a lot of attention to my dreams. Unlike most others I speak with, I also tend to remember my dreams in quite a lot of detail. Dreams fascinate me. Their significance in our lives and their role as a product of true psychological make-up fascinates me.
Most people seem to agree on what dreams actually are, but there is no single scientific or biological explanation for why we dream, or what we dream. Dreams are attributed to random electrical pulses that the brain stem sends to the forebrain when we sleep. These random electrical pulses are then processed by the forebrain (possibly according to what experiences we have had- this is the interesting part), and here a dream is born.
There is a huge gap between what Biology says we are (chemicals, molecules, DNA, electrical impulses), and the world of the subconscious, the world of feelings, moods and emotions (which I will call the "other" world). The most that science can do is to map each of our moods or emotions to a chemical structure, to an excess or lack of something. But I don't think science will be able to reach deep enough into the "other" world to construct a whole theory that explains why our "other" world is so complex when all that we are is a set of molecules. This yawning gap exists in the study of dreams as well. There is no science that pinpoints exactly the cause of a particular dream, be it through brain impulses or psychological observations.
I still look for an explanation. I have neither the inclination nor the resources to line up a hundred people, put them to sleep and form my own scientific theory based on tracking what goes on inside their heads. The scientific/biological quest I shall leave to others. Here is my more abstract take on dreams, similar to the Freudian approach. When we are awake, we always suppress our emotions to some extent- this suppression is a result of how we have been conditioned by our upbringing, our society and in general what we believe minimizes the amount of chaos and disorder in our world. But when we are asleep, we are "off guard". Our subconscious lets out all that has been suppressed- our greatest desires, our worst fears, things that fascinate us the most. Dreams are in a way journeys of self-discovery. Dreams are where we tell ourselves the truths that we choose not to hear otherwise.
Dreams have played a great part in history, mythology and literatre, most often as a sign of events to come. In the Mahaabhaarat, Gaandhaari dreams of a hundred dead bodies around a berry tree, signaling the war of Kurukshetr, that was to follow. In Shakespeare's Julius Caeser , Caesar's wife has a dream of something terrible happening to Caesar, and begs him not to go to the Capitol. He does not listen to her, and he is killed.
Finally, the image here is a painting that I find very beautiful. It is Jacob's dream of a ladder to heaven with angels on it.