Leopold is arguing that the first four grades with their inherent dissociation from the land, and the relative nonexistence of the fifth among recreationists, pose a huge threat to the lands on which we recreate. The lower recreation grades,
“consume their resource base; the higher grades, at least to a degree, create their own satisfactions with little or no attrition of land or life. It is the expansion of transport without a corresponding growth of perception that threatens us with qualitative bankruptcy of the recreational process. Recreational development is a job not of building roads into lovely country, but of building receptivity into the still unlovely human mind.”
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