This is a quote from the book "The ​Virtue Of Selfishness" by Ayn Rand
...at he is rational, the hierarchical order of his values is rational: that is, he values things in proportion to their importance in serving his life and well-being. That which is inimical to his life and well-being, that which is inimical to his nature and needs as a living being, he devalues.

Conversely, one of the characteristics of mental illness is a distorted value s
tructure; the neurotic does not value things according to their objective merit, in relation to his nature and needs; he frequently values the very things that will lead him to self-destruction....
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