Two possible explanations, depending on the context, are:
1. It's a line from a film called "Life of Brian". You'll need to watch the film to see the context! Essentially, it can be interpreted as - some people are following a particular trend just because they can see others doing it, without actually taking the trouble to find out what exactly it all means. If they did stop and think about it, they would discover that what they are doing is worthless.
2. The gourd is 'the drinking gourd', which is another name for a group of stars otherwise known as The Big Dipper. Following it would lead you towards the north.