Regards,
Ussher erred by giving a precise date, month, day, and year to the creation of man. Precise dates appeal to the needs of primitive and uneducated people. There is absolutely no way that one could get a precise date even using the methods he used of the generations given in the Bible. So maybe by those measures creation was somewhere around 6,000 years ago, but I like the more interesting arguments given in the article.