Mental Heuristics (rule of thumb)

If you can't find a solution, change the rules.
Comment: Remember that there are no no-win scenarios.

If you cannot do anything about something, there is no point in worrying about it.
Comment: Worrying is stressful, and in most situations doesn't accomplish anything - it just wastes energy. Instead of worrying about things, either do something about them or find ways around the problem. One useful idea is to write down your worries on slips of paper, and then put them away in a box. Regularly, once a week or so, you open the box and see what you can do about the worries that are still relevant.

Listen to your intuition, but do not believe it unconditionally
Comments: Intuitive or emotional thinking, analogies, "gut feelings" or "flashes of inspiration" can sometimes give fantastic new insights or show problems from a new direction. Unfortunately such thinking isn't always reliable, and quite often completely wrong! Such insights should never be accepted because you admire their beauty or they are intuitive, only because they fit with reality.