Mountains are a natural high. You can look down at the valleys beneath and see how insignificant we really are (don't go too high or you get to the death zone which is where nature proves how insignificant we are by killing us). Spending time on the moral high ground has a similar bracing effect for the self-righteous.
In life, you get the height of fashion and sophistication, although you also get the height of stupidity which, hardly surprisingly, resides on the same mountain top. Far below, you have the depths of depravity, despair and Gloucestershire. The main attraction of 4x4s is not driving up mountains but sitting high enough to look over garden fences. If there were a 12x4 car that carried four people 12ft high so you could see into people's bedrooms, this would be even more popular.
Feeling up or down is largely due to our relationship with the great and ancient god of gravity. Once space travel becomes the norm, it will be inadvisable for the depressed to travel to large planets because their hearts will feel even heavier.
A breath of fresh air always makes you feel slightly better because it increases your natural buoyancy. Sighing, on the other hand, is nature's way of discharging your ballast tanks like a submarine to make you sink lower. We all carry the world on our shoulders; it's called our head and it, too, is round, continually turning and teeming with life. When you've got the world on your shoulders, just be glad it's not on your foot.
Drug-taking is a way of getting as high as a kite. Kite flying itself is equally effective, with similar ups and downs but markedly less long-term paranoia. Some prescription drugs cancel out life's highs and lows by smoothing everything out. These drugs have been very successful and it makes you wonder if the person who invented them is very happy about it or doesn't really feel anything.
Some people seem to be naturally high on life without any form of artificial stimulant. They don't even seem to cry inside. However, nature has to balance things and you'll generally find the corresponding misery in the people who have to spend a lot of time with them.
