Maybe German-grammar should copy or import the English-grammar concepts of the "bare/plain infinitives = 'to"-less infinitives" and " 'to'-ed/accompanied infinitives"."Das Gehen" is a noun. It does not matter that it is derived from a verb.
"Zu gehen" is an infinitive.
Examples of the former: I cannot swim/tell. Go tell him.
(German had these too, didn't it? The "um ... zu ~" constructions or something lacked the "zu". Or was it that they lacked the "um"?)