pig behavior

Question
I have a 2 year old pot belly pig that I love!  However, he had some aggressive tendencies which I was able to correct through reading and implementing steps in Pricilla Valentine's book.  In her book, she states that indoor pigs tend to be more agressive because they spend more time with the humans; however my pig tends to be more aggressive the less time I spend with him.  Is there something I am not doing right as pig owner or is it his personality?  Thank you for your time.

Answer
It could be the pig's personality. Some pigs are more loving than others, some have moods.
Pigs can reproduce at a just a few weeks old, but they really don't become "adults" until they reach 2 - 3 years of age. At that age they are ready to start "moving up" in the pig hierarchy, and may try challenging authority. I've seen this happen with my barn pigs, when the youngest reached age 3 he fought his way from the bottom rung of the pig ladder to second in command in a matter of months by constantly challenging the other pigs. So it's possible that your piggy is trying to move up in rank.
Yet another possibility is pain or discomfort. Pigs can get very grumpy when they hurt and don't feel well. A neutered 2 year old male will have tusks that have pierced the gum and may be irritating his mouth, so look inside there if you can.
Each pig is an individual. I am assuming that his environment has been stable, no major relocations or new people or pets or schedules. He may be going through a difficult piggy adolescence, spending a little extra time with him re-enforcing that you are the top hog might be the solution. Teaching pigs tricks helps both the pig and the person learn to communicate with each other. It give the pig something to do and think about, and re-enforces the fact that the human is in charge. So you might try spending a few extra minutes with him every day doing a few simple tricks.