Humans are biased towards optimism.
Humans are biased towards the path of least resistance. This is the Principle of Least effort in actions.
Humans rationalize things. When making decisions, the goal is not to pick the correct option, but to justify the choice made.
Most biases can be explained by What you see is all there is. Humans ignore external information that would help, and instead jump to conclusions.

Topics

Association Fallacy - the tendency to believe that the properties of one thing must also be the properties of another thing if both belong to the same group.
Anchoring Bias - the tendency to rely too heavily on one source of information (the anchor) for decision making.
Apophenia - the tendency to perceive meaningful connections between unrelated things.
Availability Heuristic - humans are immediately biased to information that is readily available or perceptible.
Cognitive Dissonance - humans attempt to rationalize their contradictory behavior in an effort to appear more rational or to resolve dissonance.
Confirmation Bias - humans are biased towards confirming their beliefs rather than denying the alternatives, usually because doing the former is much easier than doing the latter.
Egocentric Biases - humans are prone to looking inward rather than outward. They overestimate themselves and underestimate others or their environment.
Extension Neglect - the tendency to ignore sample size.
False Priors - humans are prone to ignoring implicit assumptions about a situation.
Framing Effect - humans choose based on appearances, how things are presented, rather than how things actually are.
Logical Fallacy Biases - humans are not logical beings. Humans are not good at statistics.
Prospect Theory - humans evaluate losses differently compared to equivalent gains. Losses are weighted heavily.
Other Biases

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