Heresies

What is a heresy? A heresy is the obstinate denial by a baptized person of some truth that must be believed with divine faith. Heresies were extremely popular in the early years of the Church. There are not as much heresies nowadays, but there are still some. The early heresies mainly focused on attacking the nature of Jesus. Some thought that he didn't have a human mind or will (Apollinarism), and some thought that he was two people each with a divine and human nature (Nestorianism). I wasn't planning on talking about early heresies  because most high school theology classes teach those. I was going to focus on later heresies. One interesting one i found out was Reincarnationism. This is the Belief that certain people are or can be reincarnations of biblical figures, such as Jesus Christ. Another popular one is Americanism-A group of related heresies which were defined as the endorsement of freedom of the press, liberalism, individualism, and separation of church and state, as an insistence upon individual initiative, what could be incompatible with the principle of Catholicism of obedience to authority. This heresy was condemned by Pope Leo XIII in 1899. All these heresies are staring to die down, and some new ones are staring to spur up. But all in all, heresies have always been around and will always be around. But, the Church will keep fighting them, and winning too. 

Here is a great site where you can read more about heresies with some good answers from some educated Catholics: http://www.catholic.com/tracts/the-great-heresies