Verses on independence of the opposites come in nearly every chapter. The instruction is first about physical effects:

II.14 It is the contacts with material things that cause heat and cold, pleasure and pain;
They come and go, impermanent as they are,
Do you endure them bravely.

Śaṅkara points out that some, such as heat and cold, register on the senses, and these are invariable effects. Other opposites like pleasure and pain are appreciated by mind, and the same thing can have varying mental effects. For instance, a given degree of heat or cold can give pleasure in one situation and pain in another. A nearby blazing fire might be intolerable on the equator, but welcome in the Arctic. Śaṅkara stresses the emotional element involved in pleasure and pain. In one of his other commentaries, he gives the example of a father delightedly lifting his newborn son high above his head; the tiny boy makes a mess all over him. The father does not resent it at all, but laughs happily.
The Gītā says that pains are to be endured bravely, realizing that they will all pass. Pleasures too are impermanent, and if they become urgent impulses, they lead to pain. Manu says that the momentary relief found in gratifying a pleasure-impulse is like trying to put out a fire by throwing liquid butter on it. The flames do indeed die down, but almost immediately they spring up again with redoubled vigour. In yoga, the pleasure/pain alternation is compared to a fever, when the sick body twists and turns to get some relief. There is a momentary pleasure experienced with each new body position, but the relief passes off quickly and the position becomes intolerable. This is not to say that sensible nursing (not indulgence) is a waste of time; it can lessen the discomfort. But there is no peace till the fever is cured. So in the world, though some shifts and manoeuvres can lessen the sufferings of life-in-illusion, there is no peace till its fever has been cured.

The Gītā analysis is that life has an underlying background of suffering, because of the felt restrictions on freedom of the spirit. To that extent it is like a prison camp, set in barren country, as many of them are. Our present attempts to extract pleasure from life-as-it-is are like the entertainments got up by prisoners from time to time: songs, plays, charades, skits and so on. They have almost no material, but somehow they improvise. It is a brave attempt to forget the prison, a conscious return to childhood. For a short time there can be a real delight in preparing and watching these things. They are a splendid defiance of the sufferings of the situation.
But suppose the guards have abandoned the camp during the night, because their own side is retreating. Now there is nothing to stop prisoners from walking out. The guards may have delayed this by putting dummies in the watchtowers, which are still apparently manned. When this is discovered, to put on a camp show would be merely silly. The proper joy would be in preparing for the journey across the semi-desert, to join the friendly forces. That is, yoga.
Another example, given by Śaṅkara, is eating poisoned sweets. One who does not know about the poison eats happily; the pain comes only later. One who knows has a background of suffering all the time, though he too gets the tiny enjoyment from the sweetness. Why would he eat it? We see today how some diabetics cannot resist sweets which they know are poison for them. But if they are clear-minded, they soon correct the tendency to lapse.
A third pair of opposites, more dangerous because more subtle, is honour-and-power and disgrace. Acts of kindness may be powered by a hidden desire to dominate, or to be admired. Such subtle pleasures may be aimed at only semi-consciously, but their influence goes deep. Similarly many people find disgrace and scorn harder to bear than physical pain. A deep physical wound, if washed and protected by a bandage, will generally heal in the end. But wounds left by venomous tongues may never heal, because they are constantly re-opened in memory. Dr Shastri remarked that one of the tests of a really great man is that he can pass through a hail of slander and ridicule without losing his inner balance.
How is independence to be practised? It is recommended to begin with small things: to miss a meal occasionally, going on to fasting one day a month; to sit up once a month for two or three hours in meditation, going on to a whole night of study and meditation. (Gamblers have no difficulty in sitting up all night for their addiction.)
However, if such things are individually chosen, they lose some of their value. Most of us choose only what we feel we shall be good at. Trainers in physical skills know well that it is essential to tackle the weak points; few people will do this on their own, and a teacher is a great help. It should be added that some pupils, when the teacher insists on their practising at the weak points, instead of the strong ones where they can shine, claim that the teacher does not ‘understand’ them. Later they are grateful to him.
However, for sincere aspirants, the situations of life become teachers. If they are taken as occasions for practice of independence, the development will be complete. When caught in a storm without a raincoat or any shelter, to walk straight ahead, without futile inner complaints, is practice; to try to feel the inner Self independent of the body, is spiritual practice.
It is well known that in a crisis, physical pains are hardly noticed; the same thing can happen also in a calm environment. The Hungarian chess master Maroczy had a fine moustache, of which he was proud. During one tournament game he was resting his chin on his right hand, in an attitude common among chessplayers. But it was observed that he was slowly pulling out the hairs of the right side of his moustache, one by one, as he considered his moves. It is an exquisitely painful little operation, but he was unconscious of that. No one dared to interrupt. At the end of the game he was amazed to find blood on his face, and half his moustache gone. He now had to shave off the other half. Such incidents, showing the overwhelming importance of the mental element in apparently basic physical experiences, are not too infrequent. It is worth collecting a few from reports in the Press or books, to help cultivate independence.
Again, even severe pain is bearable if it is undergone voluntarily, and for a constructive purpose. A sprinter sometimes collapses in agony at the end of a race; it may take some time to recover. When he does, he immediately wants to race again. If the same pain were forcibly inflicted on him by a third party, it would rightly be called torture.
In one tradition, a yogin who has to face severe pain is recommended to slow down and deepen his breathing for at least ten minutes beforehand. At the actual moment, he is to hold his breath. Where it is feasible, this can take the keen edge off pain.
Śaṅkara adds a new element to the bare practice of courageous independence, as taught in the early chapters of the Gītā. This is, that all experiences and events are to be taken as from the hand of the Lord. It is not a question of praying that the circumstances may be changed, but to take them as they are, as opportunities for spiritual growth. We may take vigorous action to improve unfavourable surroundings, but in so far as they cannot be changed, the hand of the Lord is seen even in difficulties and sufferings. Then the suffering will be reduced, and an underlying joy glimpsed.
One may think: ‘If the adverse or frightening things stay as they are, the suffering will stay as it is. Ideas about the Lord will not make any actual difference.’ But they will: the situation is transformed. There is an example from one of the traditional knightly arts of Japan.
Up to some fifty years ago, in the art called Judo, to attain First Dan, with the right to wear a Black Belt, was a great event in a pupil’s life. (The standard required for First Dan was then higher than today.) Some of the young men who got it could become excited, and the teacher and seniors of their practice hall used to take measures to deflate that first euphoria. When the new Dan came on to the mats, with his brand new belt, the old teacher would call him for a practice. Now there are certain rather rough techniques which were never shown in the early years, and the teacher would use a couple of these to surprise and throw the youngster very heavily. After that practice, before he could even get his breath, he would be called out by a tough senior, again using contest tricks which he had never seen. Then another of the contest team, and yet another. By this time he would be dripping with sweat, totally exhausted, and frightened. These experienced contest experts, so genial before, now were frowning and apparently trying to injure him. Perhaps they don’t want another Black Belt, and are trying to get rid of me? They are running wild. All sorts of panicky thoughts. Many who passed through this experience have testified how bewildering and terrifying it could be.
No help from anyone. Then looking despairingly round the hall, he sees the old teacher standing with his arms folded, watching. The discipline in the training hall is absolute. If that teacher clapped his hands once, everyone would stand perfectly still. Suddenly the victim knows, that all this is controlled, watched, and somehow for his own good: it will never go too far. His muscles ache, he is still exhausted, still gasping for breath. But he knows that this is for him, not for them, and he is grateful, and – a long way down – he is content.
Life/death is one of the great pairs of opposites. The yoga does not recommend mere faith in immortality: faith, like any other idea, is liable to change when unsupported. By samādhi meditation and other practices of karma-yoga, the yogin must attain a glimpse of immortality in this very life. Such a direct glimpse will free him from the fear of annihilation. This is the final complete independence of the opposites.

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