Intelligent discontent is the mainspring of civilization. Progress is born of agitation. It is agitation or stagnation.

Intelligent discontent is the mainspring of civilization.

Healthy discontent is the prelude to progress.

Restlessness is discontent — and discontent is the first necessity of progress. Show me a thoroughly satisfied man — and I will show you a failure.

Discontent is the first necessity of progress.

Healthy discontent is the prelude to progress.