Is there a way to objectively measure

pain? Like, if you hit your finger with a hammer you suffer 5.7 units of pain?

I think I understand what he's talking about. He wants to understand the variance between comfort and extreme agony via a measurement scale.

If I had to describe this to you and how it works it would be like the following.

1) there is a steady flow of energy through our nervous system at any given point.
2) we are able to understand comfort via the limited variance.
3) we are able to understand pain via the changes in this variance.
4) this flow operates on repetition just like a radar; it sends out a signal in order to receive that pulse, whereupon receiving that pulse just like it is operating right now, when something impedes or changes the path of least resistance within that pulse the variances changes until the pulse becomes recognized as steady by the brain.
5) If the variance is outside of the known range say 10amp tolerance (+-5amps) we are able to perceive this change via knowing comfort as a baseline which is limited range of variance, and in the extreme places our awareness at an impass where a decision must be made; introversion (or loss of external awareness) or extroversion (heightened external awareness).
6) When the mind can no longer tolerate the variance of the pulse which itself operates, it begins to change its own thinking and operations; ie, the tolerance range of comfort is altered to allow for this extreme variance.
7) however, given time and experiences in comfort, this comfort tolerance range decreases and small pains can be experienced all over the body for no apparent infliction of bodily damage.

Depending upon whether we take the understanding of pain and pleasure or pain and comfort as literal or illusion is a choice we have to decide for ourselves; similar to deciding whether eating cherry ice-cream is good or bad. If it's good, use it, if it's bad, change it.

If we had to understand what pleasure is, I would say that it has nothing to do with pain (awareness of bodily changes) and comfort (absence of pain -or the ignorance of bodily changes-)

There are some things that are somewhat appearing as absolute such as how similar things work; but for the most part, they are relative to the individual, then to the location, then to time.
The individual has his/her own perceptions/beliefs/logic/intuition based upon personal relative experiences ergo they will have relative perceptions of exactly what "pain" is to them as opposed to what "pain" is to me. Next is location where environment plays the roll of what is being allowed to be perceived. Such as the perception of cold and heat perception depending upon the climate variance between source and destination. Here is the deciding factor; time. Given a limited amount of time to adjust from being in pain to a comfortable level of tolerance the ego will begin to exhibit its fear of this change happening again and this fear of the pain will resonate within the individual. Given ample time for this occurrence to to take place; the individual will perceive only minor discomfort and eventually the change will be satisfactory and accomplished.

Conclusion:
This is why we are slow in changing anything due to strain on changing people's ego-boundaries which are attached to pain thresholds and fear thresholds. If people are living in an ever-changing state of fear, they will be less likely to grow steadily; however, given too much time and comfort there is a chance of decadence setting in and becoming comfortable in stagnation.

The resolution is a balanced state where change is taken on by the individual by choice ergo changing one's own pain and fear thresholds and expanding one's own ego-boundaries to allow for new occurrences and personal growth to take place.

Why is it vague?
If it is to apply to everything and everyone, how else might it be stated if not vaguely?

Besides, this is only the starting point of an experiment, not the end. Only the end of my preaching...maybe if I had tools to measure the wavelengths of pain and fear I would be able to analyze my choices and ergo my consequences much more accurately rather than guessing at how I feel at any given point in time. But alas, without funding, there can be no growth. Time for me to get a better job I guess. :P