A man should always have these two rules in readiness. First, to do only what the reason of your ruling and legislating faculties suggest for the service of man. Second, to change your opinion whenever anyone at hand sets you right and unsettles you in an opinion, but this change of opinion should come only because you are persuaded that something is just or to the public advantage, not because it appears pleasant or increases your reputation.
Marcus AureliusAll things are linked with one another, and this oneness is sacred; there is nothing that is not interconnected with everything else. For things are interdependent, and they combine to form this universal order. There is only one universe made up of all things, and one creator who pervades them; there is one substance and one law, namely, common reason in all thinking creatures, and all truth is one-if, as we believe, there is only one path of perfection for all beings who share the same mind.
Marcus Aurelius