My mother has been living with a neck and shoulder pain since December last year.

At its worst, the pain shoots up and down her right arm. She describes it as an electric shock. At other times, it is a dull, continual ache.

She has seen four specialists and been through numerous sessions of physiotherapy. Nobody really knows what's wrong but her condition is probably cervical spondylosis - an MRI showed that a vertebra has degenerated and is pinching on a nerve.

If the pain doesn't go away, surgery is an option. The pain has lowered her quality of life and, understandably, she wants to be rid of it.

A colleague of mine is also in pain, but of a different kind.

Last week, she went home and discovered her dog missing. The apartment had been locked, there was nobody else at home and she could not understand how her beloved beagle could have just vanished.

She later found out from a neighbour that her dog had jumped out from the balcony in the third-floor flat when she was at work.

He had been suffering from separation anxiety for some time and a thunderstorm that afternoon must have caused him to panic. He died on the spot.

To add insult to tragedy, no one had thought it proper to keep the dog's body for the owner. He was thrown into a rubbish chute and it was too late by the time she found out about this. She never got to say goodbye.

She was devastated. The pain she felt was acute.

I've often wondered which is worse - physical pain or mental pain?

The two can, of course, overlap. My mother's chronic pain has caused her worry and the thought of living with it for the rest of her life weighs heavily on her.

My colleague's mental hurt manifested itself in physical ways, too. Grief can weaken the immune system and she found herself vomiting and developing a fever soon after.

But most people would agree that these are two different types of pain.

The sharp pain of a toothache is different from the distress that fills your being when your boyfriend leaves you. The extreme pain of cancer cannot be the same as the pain of grieving the death of a loved one.

Horrible as pain is, it exists for a purpose, say scientists.

Physical pain is part of your body's defence system, so that when you experience it, you will know to disengage at once from the source of pain (backing away from a knife). You also learn to be wary of the source the next time you come close to it.

Pain serves also to signal to you that something is wrong with your body and to seek help. It also aids in the healing process as it alerts you to protect the damaged part to prevent further pain.

The purpose of mental pain is less clear. Some think mental pain, which is often the result of an emotional event, can make you more self-aware. This might lead you to seek better options in life.

Still, it is not like anyone in his right mind would willingly seek out pain, physical or mental.

LIKE everyone, I've had my share of both types of pain and, well, life would be more pleasant without pain, wouldn't you agree?

There are different types of pain and gradations of pain, and people have different pain thresholds.

As I write this, I'm shifting in my chair because of my lower back. It's not so much pain I feel as a nagging, creeping discomfort. In the scheme of things, it is a baby pain, a 1 in a pain scale of 10.

But the day before, I had a dust allergy attack which led to teary eyes, a stuffed nose and a pounding, day-long migraine. That registered a 3 in my book.

That's still minor. I've had episodes of extreme physical pain that run the gamut of descriptions - throbbing, thrombosed, sharp, almost shrill, intense, dull, heavy. That's a 6 or 7 for me.

I hope I'll never have to find out what it feels like to reach the really red zone of the pain barometer, but I don't think I'll be so lucky.

Studies have found that 50 per cent of adults with life threatening illnesses who died in hospital had to go through moderate to severe pain in the last days of their lives.

The good thing about physical pain is that, most times, it can go away, either through time healing the damaged body part or with the help of medication. And if you've ever crossed the hump of severe pain and it is gone for good, I can tell you that the feeling is wonderful.

It is not the case with mental pain. This one is a harder nut to crack because the hurt ebbs and flows and there is no Panadol you can swallow to make it go away forever.

When I was in my 20s, someone I loved very much died suddenly. Although it's been 19 years, I still can't bear to discuss it openly even though there are so many aspects of my life I have made public in this column. It hurts too much.

Suffice to say that an event like that brings mental pain. I've never been stabbed but I reckon that the feeling I got when I heard the news was the non-physical equivalent of that.

Still, mental pain does fade. Time smoothens away the raw shock. The experiences that come with just living override what was once an all-consuming event in your life.

But unlike a physical pain that has been cured, a mental hurt haunts. Just when you think you have gotten over it, something triggers a memory and the pain comes flooding back.

Other than death, the most common cause of mental anguish is, yes, we're back to that old chestnut, love.

So much of the mental pain that people carry around is due to relationship woes - the pain of misplaced love, betrayed love, unrequited love, of never being able to attain the happy-ever-after scenario you hope for, at least not in this lifetime, the pain of waiting, of missing someone so much you think your heart would break, the pain of trying to forget, the pain of wanting more love, or sex, as in the case of former New York governor Eliot Spitzer.

I've come to conclude that romantic love is actually the most silly reason to get yourself twisted up in anguish.

If you think about it, this form of pain is selfish, self-inflicted and ultimately deserved.

It is caused by an ego that believes someone else should dance to your tune and that if things don't turn out your way, it's disaster, mayhem, sorrow and pain.

But the reality is, love can't be forced. It's either there or it's not. No amount of crying, wishing and feeling pained will make it happen when it's not meant to be. So accept it, and move on.

But be that as it may.

Pain - physical and mental - is inevitable and a fact of life.

It is an unpleasant sensation but the alternative is no good, either. If you really don't want to feel any pain, you're looking at non-existence - death.

Between the two, I know which side of the road I want to be, even if I'm experiencing an 8, 9 or 10 on the Richter scale of pain.

This article was first published in The Sunday Times on Apr 6, 2008.