After you understand how the "physics" of Psionics work within the game system (the psionics of the Pathfinder and D&D 3.x systems) we can turn our attention to the moralistic "metaphysics" which will help your campaigns be better. Think of each of the three moralistic alignments having their own laws. Yes, these are the laws of the DRAGONLANCE campaign. These laws work for the morals themselves, of course players may choose how to play their own characters.
The Law of Good: "Good Redeems its Own"Edit
This law states that people who are Good will seek to forward it's goals by redeeming and recalling the lost members of the flock. Justice and Mercy are all aspects of Good's methods, bringing about the advancement of the universe through these two aspects.
Simarily, a character with good alignment views everyone in the world as being worthy of Salvation (or preservation). Those who walk in darkness has strayed off the path. They should not be killed except as a last resort, but they should be reformed or reclaimed. Most characters of good alignment do realize that they are mortal and capable of making mistakes. Any good character will slip and fall.
Dangers of good alignment is that they may become arrogant or prideful. They might decide that their way is the only way and try to force their beliefs upon others. A character of Good alignment who finds himself being overzealous and fanatical may discover that they have fallen into Darkness.
The Law of Evil: "Evil Feeds on Itself"Edit
This law is the law on how evil works. The Law works, in theory, similarly to evolutionary theory in that people who are evil believe that the strong must eliminate the weak. As a result, the chaotic evil being seeks supremacy of might in society without limit or moral constraints. A lawful evil being uses laws to apply strength ridgidly in society. As a result, people who are evil to their very core use evil to their own ends through guile or strength.
Those of Chaotic evil aligment has no loyalty to anyone, and will typically use their friends and followers for their own ends and sacrifice them to their ambitions. Thus they feed off one another. Conversely, the Lawful evil tend to believe that the strong must rule the weak. They follow the strictest of laws that dictate precisely how a person's life must be lived. Breaking these laws results in harsh punishment to keep others in line. Therefore, Lawful evil characters feed off themselves in order to sustain their societies.
The Law of Shadow: "Both Good and Evil Must Exist in Contrast"Edit
Both viewpoints must balance one another for harmony in the universe. This is the law of Shadow. After all, if either side dominates, then the universe will be all light or all darkness without any contrasts to bring any focus or purpose. This law states that the objective of the shadow is to bring diversity. Diversity of choices.
Freedom exists when one can choose either one side or the other. The Law of Shadow preserves the ability to make choices as to which path one must follow, making sure there is always a choice to a dilemma. The neutral character tends to ask little and expect little in return.
The Law of Consequence: "Cause and Effect, Sow and Harvest."Edit
This Law is simple physics, and it states that for every action, there is an equal and opposite reaction. This states that for every law obeyed, blessings will follow; and for every law transgressed, punishment is the inevitable result. Blessings and punishments come about not always immediately, but they are eventual in retrospect. It is by these four laws that life in the campaign operates on a metaphysical level.