“Breath and Breast”
There must be an unconscious association between our words (and therefore our concepts) breath and breast, as their etymologies are so close that they must have been derived from a single primitive source.
Our breath is from the root BHEREU, to stir, to warm, to boil. Hence our brew, burn, ferment and fever.
And breast is from BHREUS, to swell.
Breath – breast. Her breast and the breath of life: somewhere deep within us we know they are one.