Rationality is the characteristic of thinking and acting optimally. An agent is rational if it wields its intelligence in such a way as to maximize the convergence between its beliefs and reality; and acts on these beliefs in such a manner as to maximize its chances of achieving whatever goals it has. For humans, this means mitigating (as much as possible) the influence of cognitive biases, reflecting and acting on one's desires, and combating Akrasia.
Epistemic rationality is that part of rationality which involves cognition, e.g., updating on receiving new evidence so as to improve the correspondence between one's perception of reality and the truth about same. See The Map and The Territory.
Achieving your values. Not necessarily "your values" in the sense of being selfish values or unshared values: "your values" means anything you care about. The art of choosing actions that steer the future toward outcomes ranked higher in your preferences. LW sometimes shortens this to "winning".
For humans, instrumental rationality benefits from deliberation techniques — for identifying your better courses of action — and implementation techinques — to help you act the way you've decided upon.
- What Do We Mean By "Rationality"?
- The Martial Art of Rationality
- Your Rationality is My Business
- Why truth? And...
- All Less Wrong posts tagged "Rationality"