Mental states vs epistemological states

Epistemological states are states of degrees of knowledge in the mind. Mental states are psychological states like fear, love, etc.

I wonder how they affect each other? For instance, say that you hold two contrary ideas. Epistemologically you should have no knowledge and indeed one or both of these propositions should be rejected. Yet psychologically, they can both be accepted at different times. For instance, if I think (but do not know) that chocolate is bad I can sometimes decide that chocolate is good while holding to the idea that no chocolate is good. One can say that I implicitly believe that some chocolate is good, however where did that belief come from? It seems I concocted it from nothing. Then belief would not be based on evidence and as such, would have no epistemological value. That being the case, one must conclude that that belief would have only psychological value. Am I merely deceiving myself into thinking that I do hold these notions when I really am not, or do I really hold these two notions by some psychological power?

Is epistemology, fittingly separate from psychology or are they intimately related?

They are inevitably connected, because we do our knowing with a limited human head, and so our knowing is bound by the laws of psychology; just as we do our seeing through a pair of natural human eyes, and so our sight is limited by the laws of optics.

We can overcome the limitations of our eyes by an understanding and working around the laws of optics (building and using telescopes, IR cameras etc). Unfortunately in this context, the laws of human psychology are very poorly known and do not lead us to transcendence.


I’m not sure where you are deriving these definitions from. You wouldn’t find this kind of division in Thomas, for example. Not that Thomas is the be-all-and-end-all of philosophical methods, but it is a good starting point!

Fear and love are not derived from the same subject; the subject of fear is the appetite; the subject of love is the will, which is a rational power.

Belief that chocolate is good is not concocted from nothing, but from experience of chocolate. A rational judgement is brought to bear on sense experience in this case. If I understand you correctly, what you seem to be describing in the split attitude towards chocolate (that it is good and not good) will be a division of judgement based on chocolate as appetible (appealing to the senses) and chocolate as objectively good in itself, for example.

Yes, but appetite does not exclude reason and for this reason I suppose that the Thomistic philosophy of the soul doesn’t take away all the force from my question.

After all, the appetite likes chocolate and the reason tacitly ratifies such a judgement while the question of objectivity is tacitly appetible and formally rational. So in both cases reason seems divided against itself and the categorization of objects according to faculties makes no difference (since every faculty is connected to each other in act).

Thanks for the clarification. I’d be happy to explore this further with you, as it is very interesting. Are you looking for the point of unity in the soul, between the soul’s rational powers?

No, I’m just wondering how one could at least seemingly believe in both parts of a contradiction or opposing ideas?

I would say that it is not possible to hold two contraries at the same time, since the “law of non-contradiction” is a fundamental principle in philosophy. One could not, for example, hold that chocolate is both bad and good simultaneously because the two assertions contradict and cancel each other out, so to speak.

However, I would say that you could hold two seemingly contradictory propositions at the same time, but I would say that upon careful examination it would turn out that both propositions are considering X under two different aspects—which is not a violation of the non-contradiction rule. You could, for example, hold that chocolate is good (tasty) and bad (fattening) at the same time. I imagine that sometimes, these kind of aspects can be very subtle and may give the impression of two contradictory positions.

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