How to Prove Realistic Idealism.

(Hanna, 2015)

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How to Prove Realistic Idealism

Elsewhere, I’ve briefly spelled out a version of metaphysical idealism that I call, in general, realistic idealism, and in particular, weak or counterfactual transcendental idealism (Hanna, 2024a). In this essay, I want to prove realistic idealism and weak or counterfactual transcendental idealism, in eight steps.

But before we get to that, I want to say a few things about the concept of appearances, and then define what I call the manifestly real world. In her 1947 novel, Manservant and Maidservant, Ivy Compton-Burnett makes a profoundly insightful observation about the concept of appearances:

Appearances are not held to be a clue to the truth…. But we seem to have no other. (Compton-Burnett, 1947: p. 5)

As I read Compton-Burnett, she’s saying three philosophically important things: (i) that the concept of appearances is ambiguous, (ii) that according to the first or “falsidical” concept of appearances, the very idea of “an appearance” means a mere seeming, which is consistent with falsity and illusion, and (iii) that according to the second or “veridical” concept of appearances, the very idea of an appearance means that we have no clue to the truth about reality except appearances and that appearances in this sense simply are the objective things and facts. More precisely, according to the second or “veridical” concept of appearances, the very idea of an appearance means that things appear to be a certain way, precisely because they really and truly are that way. For example, if I’m Sherlock Holmes and have just solved a very subtle case and I say by way of conclusion, “it appears that Professor Moriarity is the culprit,” then Professor Moriarity manifestly really and truly is the culprit. But even less dramatically, generally speaking, necessarily, under ordinary circumstances, if Tom or Dick or Mary appears at the door, then Tom or Dick or Mary manifestly really and truly is at the door. Appearances that fall under this second or “veridical” concept of appearances are therefore what I call veridical appearances. Then, by the manifestly real world, I mean the world as it veridically appears to any or all rational human cognizers or agents.

Now for my eight-step proof of realistic idealism and weak or counterfactual transcendental idealism.

First, let’s suppose, as initial assumptions, (i) the minimal Empiricist assumption that all human cognition begins in causally-triggered sense-experience, (ii) the minimal Rationalist assumption that we rational human animals actually cognitively possess some non-empirical or a priori mental representations, and also (iii) that we have non-empirical or a priori knowledge of at least some objectively necessary truths, for example, in logic, mathematics, and metaphysics (see, e.g., Hanna, 2015: chs. 6-8, 2024b). And for expository convenience, let’s call all non-empirical or a priori mental representations, including a priori beliefs and a priori knowledge, “a priori cognitions.”

Second, what then rules out the skeptical possibility that the correspondence between the abstract, non-empirical objects and truth-making states-of-affairs on the one hand, and our a priori cognitions on the other, is nothing but a massive coincidence, i.e., a matter of sheer luck?

Third, if it is a massive coincidence, then the correspondence between our a priori cognitions and their abstract, non-empirical objects or truth-making states-of-affairs is merely accidental or contingent, and could just as easily have failed to obtain. Again for expository convenience, let’s call this deep skeptical worry The Problem of Cognitive-Semantic Luck.

Fourth, one possible solution to The Problem of Cognitive-Semantic Luck is that the abstract, non-empirical objects and states-of-affairs naturally cause our a priori cognitions. That’s the classical Empiricist or Lockean-Humean solution.

Fifth, the basic problem with the classical Empiricist solution, however, is that it’s doubly incompatible with the initial assumption that the cognitions caused by object and states of affairs are non-empirical or a priori, both in the sense that all cognitions that are manifestly really naturally caused must be empirical or a posteriori, and also in the sense that abstract, non-empirical objects and states-of-affairs, which do not exist as embedded inside spacetime, cannot enter into manifestly real natural causal relations with human cognizers, who do exist as embedded inside spacetime. In this respect, The Problem of Cognitive-Semantic Luck is a generalization of what 20^th and 21^st century epistemologists and philosophers of mathematics and logic have called call “Benacerraf’s Dilemma” (Benacerraf, 1973; see also Hanna, 2015: chs. 6-8).

Sixth, another possible solution to The Problem of Cognitive-Semantic Luck is that an all-powerful, all-knowing, and all-good or non-deceiving God exists and creates either (i) a direct non-causal cognitive relation of acquaintance, or (ii) an indirect non-relational pre-established harmony, between the abstract, non-empirical referents and truth-makers of a priori cognitions on the one hand, and those a priori cognitions on the other. I’ll call those, collectively, the Cartesian-&/or-Leibnizian solution.

Seventh, given the fact that all the proper objects of a rational but also specifically human capacity for cognition are phenomena or veridical appearances, i.e., manifestly real natural objects, and never noumena or things-in-themselves, then the appeal to a non-deceiving God and to God’s creation of humanly-inaccessible mysterious cognitive acquaintance relations or equally mysterious pre-established harmonies seems no better justified—in effect, no more than an arbitrary and question-begging appeal to a deus ex machina—than the skeptical hypothesis that the correspondence is nothing but a massive coincidence. Indeed, in the light of the implausibility of the Cartesian-&/or-Leibnizian deus ex machina-style solution, what could decisively rule out the further skeptical possibility that the correspondence is simply illusory and has been created by an Evil Demon, namely, by a God-like being who isa deceiver?

Eighth, and finally, in view of the failures of the classical Empiricist and Cartesian-&/or-Leibnizian solutions to The Problem of Cognitive-Semantic Luck, and assuming that these three possible solutions—(i) classical Empiricism, (ii) Cartesianism-&-Leibnizianism, and (ii) realistic idealism and weak or counterfactual transcendental idealism—exhaust the logical space of all the most promising and relevant solutions to The Problem, then we can conclude to the truth of realistic idealism and weak or counterfactual transcendental idealism, by philosophical abduction, i.e. inference-to-the-best-explanation, as the best overall solution.

Let me briefly elaborate the reasoning supporting this conclusion. The core of realistic idealism and weak or counterfactual transcendental idealism is The Conformity Thesis, which says that necessarily, the manifestly real world conforms to rational human minds rather than the converse. This thesis is historically inspired by the following famous or notorious text in Immanuel Kant’s Critique of Pure Reason:

Up to now it has been assumed that all our cognition must conform to the objects; but all attempts to find out something about them a priori through concepts that would extend our cognition have, on this presupposition, come to nothing. Hence let us once try whether we do not get farther with the problems of metaphysics by assuming that the object must conform to our cognition, which would agree better with the requested possibility of an a priori cognition of them, which is to establish something about objects before they are given to us…. If intuition has to conform to the [physical] constitution of the objects, then I do not see how we can know anything of them a priori; but if the object (as an object of the senses) conforms to the [mentalistic] constitution of our faculty of intuition (Anschauungsvermögens), then I can very well represent the possibility to myself. (Kant, 1781/1787/1997: p. 110,Bxvi-xvii, italics in the original, underlining added)

There are at least four distinct versions of The Conformity Thesis, ordered in term of modal strength, from strongest to weakest: (i) there is a physical-to-mental identity relation between the ontic structures of veridically apparent, phenomenal, or manifestly real physical spacetime, together with the causal-dynamic relations between veridically apparent, phenomenal, or manifestly real natural objects and natural states-of-affairs on the one hand, and the innate mentalistic structures of rational human sensibility, understanding, and reason on the other, (ii) there is a mental-to-physical logical-supervenience-without-identity relation between the innate mentalistic structures of rational human sensibility, understanding, and reason on the one hand, and the ontic structures of veridically apparent, phenomenal, or manifestly real natural spacetime together with the causal-dynamic relations between veridically apparent, phenomenal, or manifestly real natural objects and natural states-of-affairs on the other, (iii) there is a mental-to-physical isomorphism-without-either-identity-or-logical-supervenience relation between the innate mentalistic structures of rational human sensibility, understanding, and reason on the one hand, and the ontic structures of veridically apparent, phenomenal, or manifestly real natural spacetime together with the causal-dynamic relations between veridically apparent, phenomenal, or manifestly real natural objects and natural states-of-affairs on the other, or (iv) there is a physical-to-mental strong modal actualist counterfactual dependency relation between the innate mentalistic structures of rational human sensibility, understanding, and reason on the one hand, and the ontic structures of veridically apparent, phenomenal, or manifestly real natural spacetime together with the causal-dynamic relations between veridically apparent, phenomenal, or manifestly real natural objects and natural states-of-affairs on the other, such that necessarily, if the manifestly real natural world actually exists, then if rational human cognizers were also to exist, then they would be able to know the ontic structures of manifestly real natural spacetime directly through non-empirical intuition, and also would be able to know the causal-dynamic relations between manifestly real natural objects and natural states-of-affairs indirectly through concepts, judgments, and inferences. My own view is that the most philosophically defensible version of The Conformity Thesis is the conjunction of (iii) and (iv), namely, weak or counterfactual transcendental idealism.

This is principally because weak or counterfactual transcendental idealism is substantively realistic, and rejects subjective idealism and communitarian idealism alike (Hanna, 2024a). More precisely, according to weak or counterfactual transcendental idealism, anything X can be weakly or counterfactually transcendentally ideal or mind-dependent even if, and whenever, no rational human minds actually do exist. It has only to be necessarily true of X that were rational human minds to exist, then they would be able to know some fundamental stuctural things about X. Or in other words, the weak or counterfactual mind-dependence of X is just that it is necessarily really possible for X to be knowable at least partially by rational human minds like ours, were such minds to exist. But that can be true even if minds like ours do not actually exist, or indeed have never actually existed. In that way, it is perfectly really possible for the Big Bang to be weakly or counterfactually transcendentally ideal, without postulating either our metaphysically mysterious presence at the Big Bang or our anti-realistic retrospective “cognitive construction” of the Big Bang.

Metaphysical idealism can seem implausible and scary because it seems to turn the manifestly real natural universe into either a mere appearance or illusion, or else the mere imaginary construct of some individual or community. So I conclude by pointing out that realistic idealism and weak or counterfactual transcendental idealism boils down to the eminently plausible and unscary thesis that the natural universe has anthropocentricity, cognizability-by-us, and practicality-for-us built into its basic structure. After all, given that we actually exist, we couldn’t have been either logically or really impossible; therefore, the natural universe is necessarily such that we’re really possible. Or as I put it in the earlier essay I mentioned at the outset of this essay:

realistic idealism [and weak or counterfactual transcendental idealism] says that the natural universe is our metaphysical, epistemic, and practical home, and therefore that the natural universe cannot be adequately explained without reference to our real possibility. (Hanna, 2024a: p.4)

Indeed, I think that weak or counterfactual transcendental idealism is necessarily equivalent to a moderate version of the famous or notorious Anthropic Principle in recent and contemporary physics, and also that contemporary physics is explanatorily incomplete without it (see, e.g., Hanna, 2022, 2024: ch. 7).

REFERENCES

(Benacerraf, 1973). Benacerraf, P. “Mathematical Truth.” Journal of Philosophy 70: 661-680.

(Compton-Burnett, 1947). Compton-Burnett, I. Manservant and Maidservant. London: Victor Gollancz.

(Hanna, 2015). Hanna, R. Cognition, Content, and the A Priori: A Study in the Philosophy of Mind and Knowledge . THE RATIONAL HUMAN CONDITION, Vol. 5. Oxford: Oxford Univ. Press. Available online in preview HERE.

(Hanna, 2022). Hanna, R. “R. Hanna, “Can Physics Explain Physics? Anthropic Principles and Transcendental Idealism.” In L. Caranti (ed.), Kant and The Problem of Knowledge in the Contemporary World. London: Routledge. Pp. 136-145. Also available online in preview HERE.

(Hanna, 2024a). Hanna, R. “Realistic Idealism: Twelve Theses.” Unpublished MS. Available online at URL = <https://www.academia.edu/122078297/Realistic_Idealism_Twelve_Theses_July_2024_version_>.

(Hanna, 2024b). Hanna, R. “Is A Priori Knowledge Really Possible? Yes; Here’s Proof.” Unpublished MS. Available online at URL = <https://www.academia.edu/121933519/Is_A_Priori_Knowledge_Really_Possible_Yes_Heres_Proof_July_2024_version_>.

(Hanna, 2024c). Hanna, R. Science for Humans: Mind, Life, The Formal-&-Natural Sciences, and A New Concept of Nature. Berlin: Springer Nature. Available in hard-copy and Ebook at URL = <https://link.springer.com/book/10.1007/978-3-031-61113-1>.

(Kant, 1781/1787/1997). Kant. I. Critique of Pure Reason. Trans. P. Guyer and A. Wood. Cambridge: Cambridge Univ. Press. (1781 or A edition: Ak 4: 1-251; 1787 or B edition: Ak 3)

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