define 'weak'

...probably you are two weak to let go of your obsession with good health and indulge in something that really helps...probably you are too weak to let go of the grip you have on your conventional beliefs and things you learned from your adults that say 'anything that even slightly harm your body is totally rubbish'

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calling smokers weak is an old way of arguing sachi, don't deal with it the way those narrow minded people do just cos they can't understand something beyond their mindset...this is exactly like saying, killing yourself is weak, in truth, it is much more brave