
Never pitch a tent on ground next to a large paw print.Always give a child their choice between two options which are both acceptable to you.
Everyone knows at least one phrase like these that their mothers always used to say to them. They may not all be wise, or even worth remembering, but nevertheless, Rules of Thumb wants to gather up as many as possible. The service has been adding phrases and rules of thumb to a searchable database that anyone can browse through; site members can vote and comment on them.
"Count the number of times a cricket chirps in 15 seconds, and add 37." That's the temperature outdoors in Fahrenheit. The point behind a rule of thumb is to take valuable information and turn it into a short phrase that's easy to remember. The trouble with rules of thumb? There are so many that it's hard to remember which are true and which are just fairy tales.
Rules of Thumb wants to collect as many as possible and put them through the community to weed out the useful ones. The main collection has 151 categories, ranging from camping and carpentry to stocks and survival.

The author of the books "Rules of Thumb" and "Rules of Thumb 2" started the site as a way to catalog the phrases he's collected in one place. "The rain in Spain falls mainly on the plain" and "Never trust a calm dog" have made it onto the site, and the community has the opportunity to comment on the rules, vote them up ...