I accept your criticism upf, and consequently will reformulate ‘doubting’ in attempt 2. I have also uncovered an error in attempt 1, which needs to be reformulated to satisfy Clarity and Distinction.
Reformulating Attempts 1 and 2 (equilateral triangle; doubting)
Attemp 1a.
The Clear and Distinct idea of ‘Triangle.’
To be intuited as an ideal unity, that is, an universal (essence) that instantiates itself as ‘traingularity’ in every possible subset of triangle, ideal and real (mental and concrete). (Equilateral Triangle contained the combination of two clear and distinct ideas; further, equilateral triangle, even in the ideal, is itself an instantiation of the ideal unity of triangle.)
Atempt 2a.
The clear and distinct idea of ‘Doubt.’
Once again, as an ideal unity (an essence) that instantiates itself in any mental (psychological) act.
Husserl will respond, upf, that though doubt is a psychological phenomenon, the ideal unity of doubt, that is, the universal concept – that which unifies all the different mental acts of doubting – is a supra-mental object, which can be phenomenologically intuited (literally, seen with the mind). Now Husserl will grant you that it originates in the mental, that is, you need to have doubted something in order to even begin to talk about doubt, but the unity, Husserl will call this Species, is beyond any particular instantiation. Now, you mentioned whether or not this object can also be guilty of psychologism, and in my estimation I believe there is a chance that it may. Heidegger, as proffessor Stephen R. Hicks accounted to me, accuses Husserl of psychologism later on (but as of yet I do not know the particulars for I will only be studying Heidegger in a couple weeks). Is it in this case that he does so? Maybe. For it does seem like a legitimate question, although Husserl goes to great pain to deny this to be the case. Here, take a peek:
From Logical Investigations Volume I, Investigation II, Section 8.
" We do not wish to lose ourselves in erring paths of such a metaphysics. For us what is ‘in’ consciousness counts as real just as much as what is ‘outside’ of it. What is real is the individual with all its constituents (by that he means what can appear): it is something here and now. For us temporality is a sufficient mark of reality. Real being and temporal being may not be identical notions, but they coincide in extension. We do not, of course, suppose that psychical experiences are in a metaphysical sense ‘things’. But even they belong to a thinglike unity, if the traditional metaphysical conviction is right in holding that all temporal existents must be things, or must help to constitute things. Should we wish, however, to keep all metaphysics out, we may simply define ‘reality’ in terms of temporality. For the only point of importance is to oppose it to the timeless ‘being’ of the ideal.
It is further clear that the universal, as often as we speak of it, is a thing thought of by us: it is not therefore a thought-content in the sense of a real constituent in our thought-experiences, and likewise not a thought-content in the sense of intension, but is rather an object that we think of. Is it not obvious that an object, even when real and truly existent, cannot be concieved as a real part of the act which thinks it? And isn’t even the fictitious and the absurd, whenever we speak of it, something we think of? "
(… and he goes on, and on, and would like to go on for 800 years at which point he might actually decide to call himself a philosopher)
Cheers