Questions of theodicy (why bad things happen to good people) are often predicated on an inadequate understanding of the distinction between pain and suffering. The two are different and distinct. The concept of suffering has been extensively analyzed in the medical and bio-ethical literature. Much of this work was done by Cassel.
in brief, the relevant point is that there is a distinction between
pain and suffering. Life often brings with it pain, but suffering is existential. Pain is value neutral and can even be a positive experience. Suffering, on the other hand, requires an interpretation of pain. Thus, for example, childbirth is pain but nor suffering, for it is a happy, meaningful occasion, whereas chronic back pain is suffering because it is purposeless and is so perceived. Consequently, as we often observe, even minor pain can lead to disproportional suffering, when it is interpreted as a meaningless, hopelessness, helplessness, and loss of worth. On the other hand, suffering can be turned into... just a pain, if it can interpreted as meaningful and beneficial. This teaches us that one's perceptions and interpretations of pain can make it a tolerable means to some meaningful benefit, or can turn it into exquisite suffering.
If so, animals cannot suffer for they cannot judge or interpret pain. Sure, animals feel pain. People under anesthesia also often feel pain; their heart rate and blood pressure can be demonstrated to go up, especially when anesthesia is light, but they do not suffer because their cerebrums are turned off. The
question why animals suffer pain, however, is of a different magnitude of impact
than the one of why they undergo suffering.
Here is a brief review of Cassel's work from medscape:
A major voice in recognition of the ethical perspectives on pain and suffering has been Dr. Eric Cassell. His classic article "The Nature of Suffering and the Goals of Medicine" was published in The New England Journal of Medicine initially, and later as a text (Cassell, 1982). Cassell contributed to the attention to the problem of pain and suffering. Cassell argued that there are four essential ideas related to patients who are in pain and who are suffering. The first is that "suffering is experienced by persons." He described the historical separation of mind and body and the limiting of personhood if we ignore the subjective context. Cassell suggested that understanding the place of the person in pain requires that we reject the historical dualism of mind and body. His second contention is that "suffering occurs when an impending destruction of the person is perceived; it continues until the threat of disintegration is past or until the integrity of the person can be restored in some other manner" (Cassell, 1982). This philosophy relates closely to the patient in pain who feels the underlying causes of the pain and the destruction of the body and spirit with enduring, unrelieved pain. Cassell has written about suffering beyond the physical. He defines suffering as "a state of severe distress associated with events that threaten the intactness of the person." Finally, Cassell states that suffering can occur in relationship to any aspect of the person.

Hi! You might be interested in my blog post citicizing Cassell's conception of suffering at http://aboutsuffering.blogspot.com/2007_01_01_archive.html.
Posted by: Robert Daoust | February 26, 2008 at 10:07 PM
Guess your right that pain and suffering do not always go hand in hand.
Posted by: Ajlouny | July 14, 2009 at 01:07 AM
You may suffer when you feel pain, but you can suffer without pain. =)
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