Z:gnu-www-ja-gpl-faq--102367-We think it is wrong to take b/en

We think it is wrong to take back permissions already granted, except due to a violation. If your freedom could be revoked, then it isn't really freedom. Thus, if you get a copy of a program version under one version of a license, you should always have the rights granted by that version of the license. Releasing under &ldquo;GPL version N or any later version&rdquo; upholds that principle.