If you read the article, you'll see that these are not individual points, but sequential stages that the author went through while learning what it really takes

If you read the article, you'll see that these are not individual points, but sequential stages that the author went through while learning what it really takes to be social. So stage 1. was his first attempt, then he decided 2. worked better .. etc. until he finally reached the one that worked best, i.e. 6.