Left-wing and right-wing biases
These are my hypotheses about how one could summarize the typical directions of political bias.

Left-wing:

• The weak are always justified in their actions or claims; the strong are always at fault and must bear the blame and the responsibility.
  
• If we have a problem in the society, the solution is government action that will directly regulate the problem. (For example, if the problem is that some people are poor, the solution is to create a government agency that will directly give money to these people.)
  
• Intentions behind a proposed policy are important - but the actually observed results and consequences of that policy are unimportant. Intentions (but not results) justify the means.
  
• The spectrum of morally acceptable political opinion begins at radical anarcho-communist revolutionaries and ends at moderate liberals, which makes left liberals appear to be at the political center. Marxist revolutionaries are "leftist". Left liberals are "centrist". Political centrists are "to the right". All conservatives are "far right".
  
• Proponents of right-wing views are egotistical and/or morally evil: they refuse to adopt measures intended for the good of all people. (For example, right-wing politicians oppose the minimum wage laws because these rich people hate and despise the poor minimum-wage workers and do not wish them to rise to prosperity.)
  

Right-wing:

• Existing traditions (religion, custom, etc., the more ancient the better) are always right. Any proposed changes based on a "social theory" or "scientific research" are most likely dangerous for the well-being of the society.
  
• If we have a problem in the society, the best solution is free enterprise and free market with very little government intervention. (For example, if the problem is that some people are poor, the solution is to promote job growth in the free market by removing the government regulations and lowering taxes for businesses.)
  
• Economic efficiency is the only social goal.
  
• Proponents of left-wing political views are intellectually stupid: they don't understand (despite all evidence) that the left-wing policy measures won't bring the hoped-for results. (For example, left-wing politicians who advocate minimum-wage laws don't understand, despite all evidence, that minimum wage laws will increase unemployment precisely among the poor people working at low-paying jobs.)
  

Anything else?