four directions independent and opposed aspects

• four causes of Aristotle: formal, efficient, material, and final
• "aspect" implies a direction from which something is viewed.

• to decide which pairs are opposite, we shall r. fer to the two dichotomies of general versus particular, and projective versus objective.
• Four aspects are necessary and sufficient for the analysis of a situation ... formally related, aspects 90 degrees apart are independent of one another .. aspects at opposite ends of an axis are mutually opposed.
• This idea can be illustrated by reference to the four directions. We can move due east without moving north or south, but not without moving away from, or negating, west .. the direction in which the traveler wants to go is like a compass reading — an orientation
• four kinds of relationship between knower and known