Aureus said:
Whether a subject is reacting rationally to the information, experience, and physical perceptions they have is the only measure by which someone's sanity can be made.
Yes, but you aren't defining Rationality. It is subjective, because rationality is tied to how you view the world and how you view the world is tied to how the environment TEACHES YOU to view the world.
What you have said above means that two people doing exactly the same thing can both be sane, insane or one of each depending on what their personal view of Rational is. Which makes it virtually impossible to ascertain.
Is rationality non-self destructive behaviour? A monkey acts irrationally if it jumps of a mountain, because it will die. However you can perform ostensibly self destructive things for rational reasons - cutting your arm off to escape an avalanche.
So, what exactly IS rationality? Seeing as how it differs from person to person and people can change their 'rationality' throughout their lives (as simple as kids believing in santa to realising its mum and dad, or a born again christian) it isn't a very easy thing to quantify.
Hellebore