How can we measure pain?

"It's either physical or psychological, but either way, pain cannot be measured and only the reaction to it can be seen. Psychological pain can cause physical pain, a heart attack or breakdown and possibly suicide. Physical pain can be staved almost instantaneously with drugs like morphine. But how intense is the pain, can it be measured?

....or the physical pain of yesterday, say arthritic, or my psychological pain of today. The individual's feeling of pain maybe over or under emphasized, the individual's attitude to it influences his/her actions. If we all took a day off work when we felt 'pain' the world's economy would grind to a halt.

One person's misery is another's depression, but the two are distinctly different. How is the pain of depression measured? The only scales we have are up to "acute" or "manic", but do the doctors actually work on a scale of 1 to 10?

Some people continue through intense pain, some give in at the slightest hint. But how can we measure pain?"

ACL, November 2012