Your idea of each situation, your feelings and state of mind are all reflected in your body's posture and gesture langauge. If you keep your body fixed and unreactive, your state of mind gets fixed too and so it isn't the best possible for each situation but a kind of kkrrrrhhhhhh non-working, agitating, non-comfortable which makes things in life feel like a burden and which makes your feelings largely negative.
Instead let your body find it's own comfortable yet lively position each moment. Follow your feelings, be social in natural instinctive ways, enjoy the practical sensed side of life: of feelings and sensations.
In social life being relaxed and lively makes you copy from others and makes you so understand their perspectives better. And it makes your cooperation much better. Similarly with all views and all things that you come across in your life, you can choose a perspective that is suited for just those things - but you can do so only if you are bodily relaxed and lively. So you can meet the things in life in wisest possible ways and so you are continually happier.
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