The way I read the above definition, imaginative variation is essentially a method and a set of heuristics used for plausible inference in phenomenology.  An analogy in mathematics is described in Polya's classics How to Solve It and Patterns of Plausible Inference.  Although not exactly answering all of your questions, I am sure, you will find Polya's rigour in analyzing heuristics very stimulating--and perhaps will view this as one way of applying imaginative variation to study of imaginative variation.

Donald Ihde, in his book Experimental Phenomenology (2012), gives some examples using multistable figures.

I am not quite sure, are you referring to the Cartesian Meditations? 

Husserl introduced the eidetic Variation in Ideas I as a method to reveal the essentials of an intentional object by way of an imagination that adds and takes from the object to determine what would be needed in order for the object to still remain the same and what could be taken away without the object loosing its character as that object.

Is that what you had in mind - if so, let me know and I can point you to the relevant passages and secondary literature.

best

Hi Tom. Thanks for the reply. And this is the difficulty with this matter sometimes. :) It seems authors coming after Husserl who use his concepts or ideas, sometimes also vary the terms a bit. But yes, I believe eidetic Variation is the same concept, and I would be interested both in secondary literature and also 1st person accounts of actually doing eidetic variation in a phenomenological study. Cheers Tom.

Marko,

I've always distrusted the phenomenological emphasis on imaginative variation because it is so easy for the mind to conjure up nonsense. A much better route is to rely on actual experience--to discover body-subject, for example, shifting a thing that has a place to a new place. This exercise may seem trivial but it can lead to important lived insights on the lived body, lived situatedness, and place.

David Seamon

The eidetic variation as in Descartes' wax argument is really a very primitive scientific thought experiment. A far more advanced determination of essence is the rigorous chemical analysis showing for instance that water is an accumulation of H2O molecules in the liquid state provided the pressure and the temperature are kept within well derermined limits.

Concentrating upon Husserl's eidetic variation - which by the way was never intended to facilitate rigorous physicalist analyses but to account for the essences (das Wesen) of that what appears consciously (i.e. that what would not be assessable to these more rigorous analyses anyway) - these have to be framed and understood within the overall phenomenological project. A good account is provided by Moran & Cohen in "The Husserl Dictionary" or in Gander's "Husserl-Lexikon". Especially the latter one provides an excellent list of further reading reading the topic - but as I said - it need to be kept within the realms of what Husserl intended it for and that is the question of how something that is outside of consciousness (that transcends it) could ever become immanent to consciousness and what the conditions for this are.

Best

Thomas

Hi Tom. Something that is outside of consciousness becomes immanent by a learning process. In scientific discovery, the scientist projects some meaning or judgment on the object in the form of a hypothesis and the experiment is an act of apprehension in which the object gives some meaniig to the scientist by an intuitive act. The experimental result either confirms or contradicts the hypothesis.  In Husserl's terminology,  the scientific hypothesis can be considered as an empty intentionality and the experimental act of apprehension as a categorial intuition.  My claim is  that both the empty intentionality and the categorial intuition of the scientist are far more advanced  than that of a scientifically uneducated person..Therefore, the scientist is far better equipped to describe the essence of things than the layman. I fail to see any contradiction here between phenomenology and science.

Best

Harry

Hi Harry,

you speak about the projecting of some meaning of judgment upon an object or a matter of facts. Exactly that - as I am sure you knew already - is what Husserl is interested in, i.e. the question of how this relation between the subject and the object has to be - it's a priori conditions for the possibility - in order to facilitate such a positing judgement. He tries to elucidate this (intentional) relationship by use of his break with the natural attitude via the epoche to abstain from the positioning of the object, but also of the subject to clearly focus upon the relationship only. This is where the eidetic variation comes in to clarify the results, and to purify these of mere contingencies.

I like your claim about the scientists advanced ability to perform an eidetic variation, but I am not quite sure if that was what Husserl had in mind. However, I see your point in relation to scientific questions where a sufficient scientific training would probably allow for a finer-grained assessment of the object under examination - but granting this would come at the expense that one would not attend the experiences as they present themselves, but would attend these while being posited as a scientist. If that were the case, then all so-derived results would be 'polluted' with this scientific stance, they would be situated and thus not totally free of contingencies. But that is a very phenomenological way of looking at it while your solution has - for the day-to-day business of the scientist - an appealing charm.

Best

Tom

I wonder whether the terminology and concept of “eidetic variation” were (consciously or subconsciously) borrowed from mathematics. Recall that Husserl’s doctoral work was precisely on the Calculus of Variations. In Physics applications, the Calculus of Variations presents an alternative view of a physical law. For example, according to Newton the motion of a particle obeys at every instant the proportionality of the instantaneous value of the force with the instantaneous value of the acceleration. The Calculus of Variations gives a completely different explanation of the same phenomenon. According to the Hamilton-Lagrange principle, the particle minimizes along its whole trajectory the integrated difference L between its kinetic and potential energies. How is this checked? You take a candidate trajectory, keep its ends fixed, and give it a small “variation”. If the change of L is null (to a first degree of approximation) for all possible small variations, you‘ve got the true trajectory. This idea, certainly familiar to Husserl, is suspiciously close to the “technique” of eidetic variation. But I wish Husserl had been more clear in his philosoppy than he was in his impeccable mathematics. I guess that in the back of his (prodigious) mind, he may have meant that if you want to know whether you have reached the “true” eidos, you give a small variation to each of its elements, and check whether the eidos remains the same. Then you know you are there. This doesn’t make much sense, but (somewhat humorously, if you allow me) neither does anything else that the master said.

Husserl was probably inspired by Leibniz's rational methods of decision making. See: https://philarchive.org/archive/ROILORv1 . Leibniz is the inventor calculus. One of his methods of decision making was the determination of optimums by the calculus of variations. Husserl was not very clear, probably because he had not much to add to what was already discovered by Leibniz, with respect to imaginative variation.