to further illustrate extended cognition, clark uses two anecdotal examples: inga and otto, the latter being a patient of alzheimer's disease. both desire to visit a museum and must remember the address. for inga, this is a matter of simple memory recall and accessing her belief in where she remembers the given location of the museum. due to his condition, otto relies on the use of written records in a notebook in order to recall his memory, as the disease makes it difficult for him to have a finite belief on the museum's location without it. this notebook in a way becomes his livelihood, functioning as a memory bank to accommodate his condition. as clark puts it, "his notebook plays the role usually played by a biological memory" effectively becoming a part of his extended mind. the goal of describing the thought processes of inga and otto is to show multiple variations of extended cognition and how it functions differently among individuals depending on their mental biology. clark claims the key aspect that unites the cognitive process of the two individuals is that each has the initial belief on where the museum is located. although the way the verification of belief differs in practice between the two, they are still able to come up with a solution on the museum's location despite one using a source of external storage. in a later work, clark addresses any potential criticism on the process of otto's system of belief by stating that otto's impulse to consult his notebook is a similar process to that of inga consulting her recalled memory. clark also elaborates on the importance of environment when using extended cognition. he believes that the way one formalizes "beliefs" is, "constituted partly by features of the environment" if they are playing the desired role of "driving cognitive processes.” this summarizes his belief that the mind, in fact, can extend to the surrounding environment.