# Adaequatio (Adequateness) > *Adaequatio*: the understanding of the knower must be _adequate_ to the thing to be known. SEE ALSO: [[Affordances]], [[Requisite Variety]] *Adaequatio* is a perspective on human perception and knowledge offered by philosopher E.F. Schumacher. He suggests that we can only perceive and know something if we have an adequate capacity (see a related idea in [[Requisite Variety]]): > Nothing can be known without there being an appropriate “instrument” in the makeup of the knower. This is the Great Truth of *“adaequatio”* (adequateness)…the understanding of the knower must be _adequate_ to the thing to be known. (Schumacher 1977) This idea is also closely related to the concept of [[Affordances]], which also suggests that any animal is in conversation with its environment, and that the action-potential any environment "affords" will depend on the qualities and capacities of the animal involved. --- ## Sources - Schumacher, E. F. _A Guide for the Perplexed_. 1st ed. New York: Harper & Row, 1977. ## Tags (click to view related pages) #frameworks #sapling