Feelings must be mutable. Otherwise they would be other things. For instance, a stone is generally unchanging. But, of course, a stone is not a feeling. And a stone has not the vaguest trait of any feeling. Actually, a stone is one of the most distant things from feelings. In other words, it is in the very nature (essence) of feelings to be variable and fluctuating. Being as they are, they also make our life unpredictable and even exciting. Actually, they could make our life miserable as well, but nonetheless animated and lively.
The changing nature of feelings does not allow for incoherence and irrationality. In fact, for Carl Gustav Jung ‘sentiment’ is one of the two rational function (the other being ‘thought’) whose basis are rational evaluations about other people, situations, events, things. For instance, feelings of love derive (mostly) from a positive appreciation regarding the loved one. Yet, sometimes we misunderstand emotions for feelings, causing great confusion and damage. Anyway, it is clear that our favourable evaluation of someone is always subject to changes. Here, it is important that the possible changes be rational (motivated). For instance, we rationally change our idea about someone if the other person’s behaviour changes dramatically. Or if we find out something which implies a negative judgement of the other person. As an example, we might discover that the other is a lier.
Feelings must be mutable. Hence, it is very strange to complain about human feelings’ unreliability. If sentiments were stable they would be immutable rocks, but instead they are fire, energy, force, drive, vigor, spirit, passion and vibrancy. Feelings are the very essence of our soul and they have to be like flowing rivers which constantly run into depths. See also the ACCEPTANCE entry in our TOPICS list.