The term ‘rational’ occupies a structurally pivotal position in the depth-psychology corpus, functioning less as a settled category than as a contested boundary marker between competing registers of mental life. Jung deploys it most systematically in Psychological Types, where ‘rational functions’—thinking and feeling—are defined by their dependence on judgment, orientation by norms, and subjection to the laws of reason, in explicit contrast to the ‘irrational’ functions of sensation and intuition. This Jungian axis directly echoes, and complicates, the much older tripartite soul-theory of Plato and Aristotle, in which the rational part legislates over spirited and appetitive parts that are non-rational yet potentially persuadable by reason. Rudolf Otto’s phenomenology of the holy introduces a decisive corrective: the rational theological predicates of divinity are genuine and important, yet they rest upon a non-rational substratum—the numinous—without which religion collapses into mere conceptual system. Fromm and Barrett both press the question from the affective side: for Fromm, ‘rational faith’ is not opposed to feeling but rooted in productive emotional and intellectual activity; for Barrett, affect structurally precedes and conditions rational deliberation at the neurological level. Aristotle’s distinction between strictly rational and derivatively rational soul-parts—developed at length by Lorenz—provides the classical conceptual architecture within which most of these debates remain implicitly staged.
a religion which recognizes and maintains such a view of God is in so far a ‘rational’ religion. Only on such terms is Belief possible in contrast to mere feeling.
Otto establishes the rational theological predicates of deity as the necessary precondition for belief, before arguing that they must nonetheless be grounded in a non-rational numinous foundation.
, The Idea of the Holy: An Inquiry into the Non-Rational Factor in the Idea of the Divine and Its Relation to the Rational, 1917thesis
By the continual living activity of its non-rational elements a religion is guarded from passing into ‘rationalism’. By being steeped in and saturated with rational elements it is guarded from sinking into fanaticism.
Otto articulates a dialectical criterion for religious maturity: the healthy tension between rational and non-rational elements, with Christianity exemplifying their optimal integration.
, The Idea of the Holy: An Inquiry into the Non-Rational Factor in the Idea of the Divine and Its Relation to the Rational, 1917thesis
intuition is an irrational function, many intuitions can afterwards be broken down into their component elements and their origin thus brought into harmony with the laws of reason.
Jung defines thinking and feeling as the rational functions par excellence while acknowledging that irrational intuitions may be retrospectively rationalized, preserving a permeable boundary.
, Psychological Types, 1921thesis
all rational communication is just as alien and repellent to him as it would be unthinkable for the rationalist to enter into a contract without mutual consultation and obligation.
Jung maps the typological conflict between rational and irrational orientations as a fundamental incomprehension that disrupts interpersonal rapport.
, Psychological Types, 1921thesis
Rational faith is a conviction which is rooted in one’s own experience of thought or feeling. Rational faith is not primarily belief in something, but the quality of certainty and firmness which our convictions have.
Fromm reconfigures ‘rational’ as a qualitative character of conviction grounded in productive emotional and intellectual experience, dissolving the opposition between reason and faith.
, The Art of Loving, 1956thesis
there is a sense in which all of the cognitive and motivating conditions of a mature human being are rational. They all belong to a part or aspect of the soul which in a way can rightly be called rational. However, this part or aspect is twofold.
Lorenz reconstructs Aristotle’s distinction between strictly rational and derivatively rational soul-parts, showing that ‘non-rational’ motivation in humans is never wholly divorced from reason’s influence.
, The Brute Within: Appetitive Desire in Plato and Aristotle, 2006thesis
something else in her struggles and exerts itself against reason, impelling her to act in a way that reason opposes.
Lorenz illustrates Aristotle’s claim that the non-rational appetitive part can resist rational direction while still being a constituent of a rational organism.
, The Brute Within: Appetitive Desire in Plato and Aristotle, 2006supporting
Affect is in the driver’s seat and rationality is a passenger. It doesn’t matter whether you’re choosing between two snacks, two job offers, two investments, or two heart surgeons.
Barrett marshals neuroscientific evidence to argue that affective body-budgeting structurally precedes and shapes rational deliberation in all domains of decision-making.
, How Emotions Are Made: The Secret Life of the Brain, 2017thesis
Aristotle’s theory of human psychology not only leaves room for, but in fact requires, a conception of non-rational cognition that is applicable to ordinarily developed, adult human beings.
Lorenz argues that non-rational cognition is not a pathological residue but a structurally necessary component of normal adult human action in Aristotle’s psychology.
, The Brute Within: Appetitive Desire in Plato and Aristotle, 2006supporting
non-rational action is analogous to rational action. One consequence of the non-rational character of animal action is that they are not capable of ‘passions’, pathê, which are perversions of rational behaviour.
Inwood traces the Stoic argument that passion, as a perversion of rational assent, is definitionally unavailable to non-rational animals, making rationality the precondition for moral failure.
, Ethics and Human Action in Early Stoicism, 1985supporting
some impressions are rational, and others non-rational. Those of rational animals are rational, while those of non-rational animals are non-rational. Rational impressions are thought processes.
The Stoic taxonomy of impressions as rational or non-rational according to the nature of the animal establishes rationality as the criterion dividing human from animal cognition.
, The Hellenistic Philosophers, 1987supporting
We need two distinct types of education, a rational one for our rational powers, and an irrational one for our irrational and emotional powers.
Sorabji reports Posidonius’s bipartite educational programme, which acknowledges that rational instruction cannot alone reform the emotional, non-rational dimension of the soul.
, Emotion and Peace of Mind: From Stoic Agitation to Christian Temptation, 2000supporting
man’s specificity, man’s essence as a rational being, as the rational animal, announces itself to itself only on the basis of thinking the end in itself.
Derrida exposes the circular anthropological dependence in Kant: the concept of man as rational being can only be instantiated through the unconditioned moral end, yet man remains the sole example of that concept.
, Margins of Philosophy, 1982supporting
The new product which the crucible gave forth was the rational, the concept.
Snell locates the historical emergence of ‘the rational’ in the Greek linguistic evolution from concrete verbal vitality to abstract conceptual clarity, making rationality a cultural-linguistic achievement.
, The discovery of the mind; the Greek origins of European, 1953supporting
boulêsis is a rational [i.e correct] orexis; thelêsis is a voluntary boulêsis.
Inwood records the Stoic technical classification of boulêsis as ‘rational desire’—correct orexis—distinguishing it from other species of practical impulse in the Stoic typology of motivation.
, Ethics and Human Action in Early Stoicism, 1985aside