Leaving the complications of the human breakfast-table out of account, in an elemental sense, the egg only exists to produce the chicken. But the chicken does not exist only in order to produce another egg. He may also exist to amuse himself, to praise God, and even to suggest ideas to a French dramatist. Being a conscious life, he is, or may be, valuable in himself.
The collected works of G.K. Chesterton (ed. Ignatius Pr, 1987) - ISBN: 9780898701470