The American Maultsby developed five rules for determining whether a thought is healthy. A healthy thought is one that meets at least three of the five rules. If a thought doesn't meet these requirements, it needs to be adjusted.

Maultsby's Five Rules:

• Is this thought based on indisputable facts?
• Does this thought protect my life and health?
• Does this thought help me to keep short and to achieve long-term goals?
• Does this thought help me avoid or handle conflicts with others?
• Does this thought help me feel in a way that is pleasant?

Maultby added:

• All rules are equally important.
• The first line does not refer to religious, existential, or philosophical thoughts.
• Healthy thoughts relate to myself and do not necessarily have to be healthy for someone else.
• The last line does not concern the use of narcotic drugs.
• Healthy thoughts may be different tomorrow.