The great learning (IM 684)

It has never been the case that what was of great importance has been slightly cared for and that what was of slight importance has been greatly cared for. This has always been true... So, everyone should be careful of their thought because thought are important as they define us. And everyone should be watchful over themselves when they are alone because it's the time when thoughts come into play. This should always be the greatest lesson one should learn.