The primitive root of the pleasure of parenthood is two-fold. On the one hand there is the feeling of part of one's own body externalised, prolonging its life beyond the death of the rest of one's body, and possibly in its turn externalising part of itself in the same fashion, and so securing the immortality of the germ-plasm. On the other hand there is an intimate blend of power and tenderness. The new creature is helpless, and there is an impulse to supply its needs, an impulse which gratifies not only the parent's love towards the child, but also the parent's desire for power.
Source: The Conquest of Happiness, 1930, chap.13:The family
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