One should think about the negative effects of ‘vishhaya-vrAta’, the gang of sense experience.
‘virajya’ : discarding them out of disgust.
‘sva-lakshhye’ : in one’s own goal.
‘manasaH niyata avasthA’ : keep the mind tethered under control
‘shama uchyate’ : is said to be ‘shama’.
In short, the control of mind is ‘shama’.
Why does the mind run after sense objects? It is because of the footprints of past experience. They are called ‘smell’ or ‘vAsanA’.
This continues life after life. This inter-life vAsanA continues in a latent form in the subtle body, even after the physical body dies.
When the soul takes another birth and thus obtains a new physical body, the latent vAsanAs begin to show their mettle! If those vAsanAs can be eradicated in toto, the mind will be calmed automatically. It is thus the Acharya defines ‘shama’ in ‘aparokshhAnubhUti’. (Just now what we gave was the definition from Viveka chudamani).
*sadaiva vAsanA-tyAgaH shamo’yam-iti shabditaH*
Abandonment always of desire-promptings through vAsanAs is said to be ‘shama.
It is enough to understand that ‘shama’ is control of the mind.