“Ye are all fruits of one tree, the leaves of one branch, the
flowers of one garden.” That is one of the most characteristic
sayings of Bahá’u’lláh, and another is like it: “Glory is not his
who loves his own country, but glory is his who loves his kind.”
Unity—unity of mankind, and of all created beings in God—is the main theme of His teaching. Here again the harmony
between true religion and science is evident. With every advance
in science the oneness of the universe and the interdependence
of its parts has become more clearly evident. The
astronomer’s domain is inseparably bound up with physicist’s,
and the physicist’s with the chemist’s, the chemist’s with
the biologist’s, the biologist’s with the psychologist’s, and so
on. Every new discovery in one field of research throws new
light on other fields. Just as physical science has shown that
every particle of matter in the universe attracts and influences
every other particle, no matter how minute or how distant, so
psychical science is finding that every soul in the universe
affects and influences every other soul. Prince Kropotkin, in
his book on Mutual Aid, shows most clearly that even among
the lower animals, mutual aid is absolutely necessary to continued
life, while in the case of man, the progress of civilization
depends on the increasing substitution of mutual aid for mutual
enmity. “Each for all and all for each” is the only principle on
which a community can prosper.