Trouble distinguishing STO vs STS

[Guardian]

STS and STO I think are better divided into emotional polarities rather than actions. Because ultimately, if I stab someone to save their life (i.e. surgery) or I stab someone because I hate them (i.e murder), they are both very different polarities even though the actions are identical.

I use this image for a frame of reference:

http://wedharma.com/wp-content/uploads/2...-Scale.jpg