The internal logic of I think therefore I am in metaphysics

I think therefore I am is a famous proposition in western philosophy, which is the start of Descartes's metaphysics systems. This Archimedes type basis points has not only pried the theory gap of the real world, but also find the reasonable logic connections between I think and I am, which gives full scope to the rational flag and makes sufficient theoretical preparations for the later development and subversion of metaphysics.