Traditionally, ethics are gained from our interaction with others, viz we learn them from our parental units. But it is not impossible to consider that ethics may be formed from a contemplation with the individual soley: the soul.
Yes indeedy there are exceptions: psychopaths are a common one. Regardless (or perhaps because) of the ethics taught during the impressionable period of mental development, these (overwelmingly male) individuals instead eschew empathy for a more direct emotional feedback: power.
Of course. All our experiences, and therefore all empirical knowledge, and all deductive and indictively reasoned knowledge based on this experience, is filtered through an individual's experiences ... just like a mind metaphor of the physical brain, where 100 billion neurons are connected via 100 trillion connections, some with upwards of 1000 dendrites (connections) each, creating links with tens of thousands of other axons (the electro-chemical bits that make the sparks). So in effect, one can only interpret the senses according to what has already been experienced.