What is Old Major's main idea or purpose in Animal Farm?

Old Major's main idea is to make the animals aware of a
transformative vision of reality.  His primary purpose was to suggest to the animals
that they can be the agents of their own state of being on the farm.  The vision Old
Major proposes is one that calls for the overthrow of the humans that own the control of
the farm.  In his vision, Old Major seeks to inspire the animals to no longer be
relegated to the periphery of decision making, but actually move to the center.  In
teaching the animals the song, "Beasts of England, Old Major reaffirms to the animals
that they can collectivize to cause change.  This is something that his "disciples" like
Snowball and Napoleon take to heart in the acting upon the call for revolution.  Old
Major's main idea is one that serves as the catalyst for the events that follow and the
advancement of the plot of the novel.