For example, some versions of internalism appeal to counterfactuals involving full rationality, but sometimes agents have certain reasons precisely because they are not fully rational.
"You could never be entirely sure he was fully rational.
If it were fully rational, it wouldn't be music.
"They fall in love with a particular boat, and it's not a fully rational thing".
IN A world of fully rational human beings, people would all be constantly checking the financial markets for profitable opportunities.
In the internal logic of brinkmanship, it can perhaps make sense to sow doubt in your opponent's head about whether you are fully rational.
Instead, Professor Simon contended that in today's complex world individuals cannot possibly process or even obtain all the information they need to make fully rational decisions.
And, despite what some E.M.H. defenders claim, the presence of a few fully rational investors isn't enough to prevent things from going haywire.
Mathematical theories such as Dr Nash's tend to assume a world populated by individuals who behave in fully rational ways, because they have perfect knowledge.
He has tried to reconcile them in the "adaptive markets hypothesis", which supposes that humans are neither fully rational nor psychologically unhinged.
"[I]t hurts to portray ourselves as too fully rational and cool-headed… That the US may become irrational and vindictive if its vital interests are attacked should be a part of the national persona we project".
