Relating Description and Explanation: The Case of Gregor Mendel

by David Fleischacker

Description and Explanation: Mendel’s Pea Plants

One good illustration of the dynamic relationship between description and explanation is found in Mendel’s breakthrough into genetics.  Description to recall is articulating how a thing relates to us.  Explanation is relation things to things.  At least that is a starting point for defining description and explanation, we can become more precise later.

Mendel’s attentiveness to the descriptive features of pea plants provided him with a starting point that led him to his formulation of an explanatory term that gave an account for some of those features.  We know these features as phenotypes.  Every phenotype is a descriptive conjugate or set of conjugates.  The color and shape of the peas and pea pods, the flower color and their positions, as well as the size of the plant were all observable traits.  Color, shape, and size are traits that relate something to us, through our motor-sensory being. Furthermore, there is something important about the particular traits Mendel selected. Each were found in one of two forms (eg. tall or short, green or yellow), and never in some type of mixed combination.  One could as well control these traits through proper breeding.  This provided a fruitful ground for asking questions, expanding observations, building explanations, testing those explanations, and asking further questions.  It was what I would call a rich descriptive matrix.

This real reason that this matrix was rich is because it was one of those zones in the world of description that provides a starting point for launching into the world of explanation.  One finds the same kinds of zones in other scientific breakthroughs. Certain descriptive accounts of gases led to atomic theory.  Moving projectiles and other similar falling objects that had a high density and relatively low friction level provided that matrix for early modern physics. Though pea plants are not the only living thing that could have provided the zone for this breakthrough into genetics, they were Mendel’s zone.

In starting with a rich descriptive matrix, notice that one is starting with conjugates in act.  A conjugate in act just means that one is dealing with real, experienced existing descriptive traits.  In Mendel’s case, he went a bit further and counted the actual frequencies of the alternatives of the seven descriptive conjugates.  He counted how many pea plants were tall and how many were short given various crossings of parents.  He could mate two tall plants or two short plants, or a tall and a short plant, and then count the frequencies of the tall and short characteristics in the offspring.  He did this for all the traits.  He performed thousands of crosses.  Notice that in counting, he also had to organize his findings into columns allowing for the discovery of patterns.  And patterns is what he found, those patterns now familiar to all of us, namely that these traits were found, depending on the parents, in distinctive ratios — either all one trait, all the other trait, three quarters one trait and one quarter the other (3:1) or half one trait, half the other (2:2).

Notice, thus far, I have stayed entirely with descriptive conjugates.  Both the actual frequencies and the surmised ideal frequencies (eg. 3:1) are based on those descriptive features.  Explanation comes later, along with an explanatory account of the statistical frequencies. The next blog will be on how these frequencies of descriptive conjugates led to the explanatory conjugates in Mendel’s moving mind.

Questions about the Relationship of Description and Explanation.

by David Fleischacker

One of the areas that I have found to need further articulation in Lonergan’s writings is that of the scope and the relationship of explanation and description.  Description is rooted in an account of things in relationship to the human motor-sensory operations.  How much of the universe can we discover through description?  What are the types of patterns that can be discovered? How does description come to grasp unity-identity-wholes?  Which types of unity-identity-wholes can be discovered by description?

Explanation in contrast is more comprehensive and its natural limit is proportionate being, though through analogy it contributes to explanatory accounts of Revelation. In general, via Lonergan’s articulation in INSIGHT, explanation deals with the relationships of things to each other.

Also, as one fills out the scope of description, what more precisely is the relationship between description and explanation, not just generically, but in a variety of fields.  There are likely patterns that will be discovered.   In INSIGHT, there is a generic account of the movement from description to explanation in the first chapter, via the account of explanatory definitions and then the move to implicit definitions.  This is advance in chapter 8, the chapter on things.  Things can be discovered and articulated in terms of descriptive and explanatory conjugates. More will be able to be said however through studies of interiority as various fields of study historically unfolded, such as in physics, chemistry, and biology.

The import on such an articulation of the relationship of description and explanation is twofold; on the one hand it will allow for a deeper grasp of the capacity of description to know being, on the other it will clarify the path that one must take to reach explanatory knowledge which liberates one more fully into the full scope of proportionate and analogical knowledge of being.

Light and Transcendence

If you glance through the liturgy of the hours and the divine office, you will notice the frequency that the word light is used.  Of course, it is in the context of prayer, and it is an attribute of Jesus Christ and of all the persons of the Holy Trinity.  It is not by accident.  Light in the physical world is the closest analogy to the spiritual that is found.  Aristotle recognized that sight is the most liberated of the senses and the one that is closest to the nature of the human mind, especially what he called the Agent Intellect and Plato called the light of Being that illumines our minds and allows us to search out and then gaze out upon the world of being that is behind and beyond the world of appearances.  St. Augustine also picks up on on this light and expands it from the light of being to the light of conscience, the light of faith, and the light of glory.  Light is at the very essence of the human soul.  St. Theresa Benedicta (Edith Stein) picks up on this in her book The Science of the Cross, and recognizes that this inner light is the essence of the human soul, and it is the inner region of the soul where God dwells, and unfortunately, the place from which we as human beings tend to be exiled.  Which means we are exiled from our selves.  But Christ wants us home, to return to abide with Him forever.  God is light. And so are we.

In terms of the transcendental notions then, these are the differentiate lights that Lonergan has articulated in an explanatory manner.  As long as we exist, that can be actuated. But they can also remain merely as a capacity for self-transcendence.  When the interior question for understanding arises with regard to an experience, then this light has awakened.  It is the same quest in which an insight emerges, and this can then be described as an illumination or an ah-ha experience.  Notice how this parallels physical light.  When light shines off into space with nothing to illumine, it seems dark. But as soon as something comes into its realm, like a moon, then it illumines the object, and suddenly our eyes have something to see.  The same with the quest for understand. And insight (act of understanding) allows the eye of the mind (as Augustine frequently uses the term), and eye intrinsic to the quest (a question is intrinsically conscious and intentional) to see (intend) something.  Furthermore, once seen, then we can speak it, and this parallels the need to conceive of the insight.

Once the insight is conceived, then a new transcendental notion can be actuated in our capacity for self-transcendence.  There are two sequences of actuated quests here. The first regards the correctness of the insight.  Is my insight into a representative democracy correct?  The second is whether we have a factual object understood by the insight.  Is our country a representative democracy? The first has to be answer correctly before the second can be answered factually.  Both arise in the quest for truth or being.  To answer this quest for truth, first one needs to gather evidence and then reach a kind of insight into whether the evidence is sufficient. Lonergan calls this a reflective insight, which traditionally is named a grasp of sufficient evidence.  Such an insight then allows one to answer the quest and pronounce a judgment.  Yes, that is the meaning of democracy.  Or yes, we live in a representative democracy.  Or maybe I realize that I do not understand the nature of a democracy, or that we do not live in one. These too are judgments, answers the that quest “Is it so?”

As the mind rises into the world of truth and being through judgment, then the possibility of a new light or transcendental notion emerges.  Judgments of fact attune us to the world that is.  Judgments on the correctness of insight not only make possible a grasp of judgments of fact, but also these open up to us worlds of possibility and even probability.  We can then wonder about doing something in light of the possibilities that could become factual.  There is as Lonergan articulates a scale of feeling that intentionally awakens to objects of fact and objects of possibility.  Naturally, these response to the greater possibility (the greater intelligibilities and factualities) with more vibrancy or more commonly, with more energy. This can become vastly disordered of course.  But nonetheless, our entire souls awaken within this light of goodness, of value, to the possibilities of our creative free participation in the coming to be of this world, and even facets of our own existence.  Appreciation, thankfulness, and love respond to this world of intelligible facts that are good.  Free decision is the possible response to intelligible possibilities and probabilities that then brings about factual goods.  This light is that of conscience.  It is the full realization of the transcendental notion of value. As the landscape of intelligibility grows, the landscape of possibility, probability, and factuality grows.  That is the growth into an entire scale and horizon of the good.

Ultimately it also is the expansion of the actuation of the entire capacity for self-transcendence that then awaken to the question about unrestricted answers to the potentially unrestricted quests. That is as Lonergan articulates in chapter 4 of Method in Theology, the emergence of the question of God.   If one has been appropriating one’s own interiority, one realizes as well that this is also an awakening to the very inner essence of one’s own soul, to the capacity for self-transcendence.  As that capacity becomes actuated, its full actuation, the full actuation of the transcendental notions, which is aptly described as an unspeakable illumination through God’s outpouring love who gives himself as a Triune self to the subject, is then a state of being in love without conditions.

I want to bring this back to the liturgy of the hours and divine office now.  This unfolding of this liturgy throughout the year cultivates the human subject, and through it, God tills the landscape of one’s horizon at all levels of conscious intentionality, from experience up through moral acts to purify the totality of one’s soul so that it is more and more permeated by the transcendental notions. Then one becomes more and more a light in this world.

The liturgy of the hours and divine office however as liturgical however revolve around an even more potent set of lights.  Those lights correctly understood and entered are the sacraments.  The sacraments are gifts from God that literally started in the motor sensory world that if rightly received permeate the entire human subject from the lowest to the highest levels of conscious intentionality, and these do so by actuating the capacity for self-transcendence in its state of being in love without restriction.  This state as long as it lasts and as much as it is lived from then increases the realization of each transcendental notion as it awakens along the paths of emerging conscious intentionality, and it transforms the entire landscape of conscious intentionality.  The Eucharist is the supreme realization of all of this.  One literally is moving into the inner reaches of the Holy Trinity. This is why it is described as an eternal banquet.  At a mass, one’s motor-sensory being literally participates in a physical encounter with that which has been transubstantiated into the ascended incarnate Son of God who opened the doors for humanity to enter the inner life of the Holy Trinity. We are literally able to move closer in space and time to this reality.  This reality though emerges into all levels of conscious intentionality through acts of faith and gifts of grace.  The Father sends His Son into us through their Holy Spirit, literally and spiritually. Is this necessary?  No.  It is a gift and promise.  God makes it possible for us to receive him into our beings in a manner similar to how Mary when Gabriel came to her and she proclaimed her fiat.  The Son was then literally conceived in her.  When we sit in the physical presence of the Holy Eucharist, the body-soul-humanity-divinity of the Son, God promises to enter us if we are rightly ordered, receptive, and pure.  It reaches its height when we say and Amen to Him, and we are feed physically and if rightly purified, spiritually with Him. As incarnate beings, this way of being given the Son then illumines the totality of our conscious intentionality in a manner like nothing else. We can then understand what someone like John Henry Newman meant when he said that our presence in and reception of the Holy Eucharist is the closest we get to heaven while on earth. It is heaven, the eternal banquet.  Now that is a light.

Just some thoughts.