The law of karma underpins the process of transmigration of the soul. Karma literally means "action," but more often refers to the accumulated reactions to activities. Thus we talk of "good karma" and "bad karma," which are stored reactions that gradually unfold to determine our unique destiny.
The self-determination and accountability of the individual soul rests on its capacity for free choice. This is exercised only in the human form. Whilst in lower species, the atman takes no moral decisions but is instead bound by instinct. Therefore, although all species of life are subject to the reactions of past activities, such karma is generated only while in the human form. Human life alone is a life of responsibility.
The Bhagavad-gita categorises karma, listing three kinds of human actions: (1) Karma: those which elevate, (2) Vikarma: those which degrade and (3) Akarma: those which create neither good nor bad reactions and thus lead to liberation.
Attaining a heavenly destination is like going on holiday; a lower birth like going to prison.
A story illustrating karma.
Trying to avoid our destiny.
"Only the actions of the just smell sweet and blossom in the dust."
James Shirley
Pious activities such as charity, penance and pilgrimage, especially when performed in anticipation of material benefits, such as a higher standard of living on earth or an elevated birth on the heavenly planets.
Avoidance of impious acts, considered to bring misfortune and degradation. These includes the neglect or abuse of five sections of society, namely women, children, animals (especially cows), saintly people, and the elderly
This statement suggests that Hindus perform pious activities largely out of fear and selfishness. It neglects the finer sentiments behind vegetarianism, such as empathy for fellow living beings.
The soul passing through lower species doesn't create any new karma. He only works off the karmic reactions generated whilst in the human form and gradually rises towards another human birth.
Not usually. Blame and responsibility are different. Karma entails understanding that we are all ultimately responsible for our own lives. Belief in karma does not automatically create indifference to the suffering of ourselves or others (as the above statement may imply), but underpins sentiments of "helping others to help themselves.
"In proportion to the extent of one's religious or irreligious actions in this life, one must enjoy or suffer the corresponding reactions of his karma in the next."
Bhagavat Purana 6.1.45