A man should never leave one camp for another until he has made a comfortable berth for himself, by way of consolation for the losses that he must expect; and in any case, a prudent politician will see his friends first, and give them his reasons for going over, and take their opinions. You can still act together; they sympathize with you, and you agree to give mutual help.
 Honoré de Balzac, Lost Illusions (1843). copy citation

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Author Honoré de Balzac
Source Lost Illusions
Topic loss reason
Date 1843
Language English
Reference
Note Translated by Ellen Marriage
Weblink https://www.gutenberg.org/cache/epub/13159/pg13159.html

Context

“"You made your right-about-face in such a way that you were bound to lose the support of the Liberal press, and the Liberals are far stronger in print than all the Ministerialist and Royalist papers put together. A man should never leave one camp for another until he has made a comfortable berth for himself, by way of consolation for the losses that he must expect; and in any case, a prudent politician will see his friends first, and give them his reasons for going over, and take their opinions. You can still act together; they sympathize with you, and you agree to give mutual help. Nathan and Merlin did that before they went over. Hawks don't pike out hawks' eyes. You were as innocent as a lamb; you will be forced to show your teeth to your new party to make anything out of them.” source