A person functioning exclusively in the Cartesian mode may be free from manifest symptoms but cannot be considered mentally healthy. Such individuals typically lead ego-centered, competitive, goal-oriented lives.
Over preoccupied with their past and future, they tend to have a limited awareness of the present and thus a limited ability to derive satisfaction from ordinary activities in everyday life. They concentrate on manipulating the external world and measure their living standard by the quantity of material possessions, while they become ever more alienated from their inner world and unable to appreciate the process of life.
For people whose existence is dominated by this mode of experience no level of wealth, power, or fame will bring genuine satisfaction, and thus they become infused with a sense of meaninglessness, futility, and even absurdity that no amount of external success can dispel.
From “The Turning Point: Science, Society and the Rising Culture” (1982) by Fritjof Capra, author of “The Tao of Physics”