Quora: Can you share your favorite YouTube video on the philosophical doctrine known as Solipsism? — This was an insincere question design to dismiss my rationality arguments as solipsism. Instead, it was helpful.
Not really.
I like René Descartes more. He’s the proper beginning, but unfortunately not the rational end. The solipsists actually blew Descartes’ amazing “I think, therefore I am” insight up. This happened because they lack free will. Descartes didn’t. In fact, his famous quote is an inadvertent declaration of his free will (see the end of this post). You see, without free will, the SELF must conclude. That’s what it does. It makes decisions. The process of reason doesn’t (does not conclude). Descartes was using reason; the solipsists weren’t.
GOOGLE – René Descartes used radical doubt [me: AKA free will] as a tool to find absolute truth, concluding that his own thinking mind is the only undeniable certainty (“I think, therefore I am”). Solipsism is the endpoint of this doubt—the philosophical theory that only one’s own mind is sure to exist, rendering the outside world and other minds unknowable.
Descartes (I think, therefore I am) and Solipsism (the philosophical theory that only one’s own mind is sure to exist) are an interesting beginning, followed by a tragic over-extension (Solipsism).
My position, of sorts, is somewhere in the middle. I am fairly sure, but not absolutely, that my position is rationality.
To wit: Absolute truth is UNCLAIMABLE (not necessarily unknowable — solipsism), but it exists absolutely (for reason to exist), and objective truth, developed using reason, is our work-in-progress towards it. Yes, it is impossible to prove absolute truth (in order to sustain reason), but —and here’s the crucial point— it IS POSSIBLE to disprove false hypotheses — absolutely. This is how it is possible to converge towards absolute truth, thereby developing objective truth. Moreover, this “absolute disproof” premise is also foundational to the scientific method; hypotheses must be falsifiable. Reality (absolute truth) insists. The complete process is summarised here:

Now, about “cogito, ergo sum.”
When an individual “sees” their thoughts, they have acquired SELF-control, which enables SELF-awareness. This is also Echert Tolle’s observation below. He sees his thoughts and hears the voice that accompanies them. Not everyone can. In their emotional immaturity, most remain automatons.

Intellectualism’s vanishing point.
Finally, the vanishing point of all Western thought, including Solipsism, is reason. Internalize that first. Then, all the pieces fit together. I promise.