Summary: The superhyperbolic doubt is the principle that ‘anything may be possible’, for that which could otherwise be believed to be absolutely (or 100%) certainly impossible at present could be possible as the intellectual capacities of the believer may be limited. That is, the proposition/s, for example, that are otherwise thought to be absolutely certainly true could be false. The superhyperbolic doubt is compared and attempted to shown to be superior to the hyperbolic Cartesian doubt and the idea/proposition that ‘anything is possible’. Furthermore, its implications are stated and discussed, the implications like ‘all axioms as 99.99% certainly true’ and ‘all mathematics as philosophy’. Since the superhyperbolic doubt is the first and the most basic principle of my superultramodern science and philosophy, it could also be referred to as the superultramodern doubt.