Michel de Montaigne,
Essays of Michel de Montaigne…
“ Who ever saw one physician approve of another's prescription, without taking something away, or adding something to it? by which they sufficiently betray their tricks, and make it manifest to us that they therein more consider their own reputation, and consequently their profit, than their patient's interest. He was a much wiser man of their tribe, who of old gave it as a rule, that only one physician should undertake a sick person; for if he do nothing to purpose, one single man's default can bring no great scandal upon the art of medicine ”
