The Theory of Illumination in St. Bonaventure

By Brother John Raymond

We see in much of St. Bonaventure’s philosophical thought a considerable influence by St. Augustine. So much so that De Wulf considers him the best representative of Augustinianism. St. Bonaventure adds Aristotelian principles to the Augustinian doctrine especially in connection with the illumination of the intellect according to Gilson. Other philosophical writers will see Platonic tendencies also in St. Bonaventure. Nevertheless, we see in the Theory of Illumination a uniquely Bonaventurian synthesis with a great influence from St. Francis. We see St. Augustine’s view of the soul looking outward at Creation, inward on itself, and up or outside itself to God developed in a much more rigorous way by St. Bonaventure. He says, "It is possible to contemplate God not only outside us and within us but also above us: outside, through vestiges of Him; within, through His image; and above, through the light that shines upon our mind".1 St. Bonaventure will take these three illuminations and show how they will lead us to God. This "light" which is quoted above is the same light talked about by St. Augustine. He says, "This is the light of Eternal Truth, since our very mind is formed immediately by Truth Itself’".2 We see this reference to St. Augustine concerning the Divine light which helps us see Eternal Truths. Unlike St. Augustine, St. Bonaventure will systematically show how the outward, inward, and upward light leads to glory, praise, and honor of the Father, Son, and Holy Spirit.

St. Bonaventure talks about a light outside of us in Creation which shines forth to reveal the power, wisdom and benevolence of God. He says, "The Supreme power, wisdom, and benevolence of the Creator shine forth in created things in so far as the bodily senses inform the interior senses".3 The shining forth in created things is done in a threefold way: by the potential excellence of things, the habitual course of things, and the actual existence of things. The bodily senses serve the intellect by seeing vestiges of God in creatures. In the potential excellence of things, man investigates rationally the weight, number, and measure of things. This leads to seeing mode, species, order, substance, power, and activity. From these vestiges one can be led to consider God’s power, wisdom, and goodness. In the habitual course of things, the world is considered according to its origin, development, and end. Again these considerations lead us to see God’s power, providence, and justice. These considerations though involve the way of faith. Finally, in the actual existence of things we contemplate intellectually a certain hierarchy of existence. We see some things merely exist; others exist and live; and others exist, live, and discern. We see things are corporeal; some partly corporeal and spiritual. We reason there must be others which are wholly spiritual. Again, we go from the changeable and corruptible to the changeable and incorruptible. This leads us to consider the unchangeable and incorruptible. This hierarchy of existence leads to the existence, living, intelligent, purely spiritual, incorruptible, and immutable God.

Another aspect of the light in Creation outside of us is seeing God in visible Creation. He is in creatures by His essence, power, and presence. We abstract from the doors of our senses that which is purely spiritual. We see an Aristotelian influence on St. Bonaventure concerning this method of abstraction. These abstracted concepts are made by reason which abstracts from place, time, and change so that we can make judgements with certitude. Certitude can only come from the Eternal Art, "by which, through which, and according to which all beautiful things are formed".4 So we go from the visible to the invisible by God’s very design of us and created things. Thus, "creatures of this visible world signify the invisible things of God... for every creature is by its very nature some kind of image and likeness of the eternal Wisdom"5. Further, we are lead to God because "the effect is the sign of the cause; the thing exemplified, of the exemplar; and the way, of the end to which it leads".6 All this light externally given to us disposes us for the next stage—to look at the Divine things that shine forth in the mirror of our minds.

As we look within at our natural powers, we see the imprint of God on our souls. St. Bonaventure says that if we consider the three powers of the soul and their relationships, we will see God through ourselves as through an image. Concerning the relationships of the three powers of the soul, St. Bonaventure goes more into the realm of Theology than philosophy. We will consider here more of the individual faculties and how they are illumined by God. The memory retains and represents to us successive, simple, and everlasting things. By the retention of the past, present, and future the memory is an image of eternity which extends itself to all times. The memory retains simple things which are the principles of continuous and discrete quantities. These principles or simple forms can only come to the memory from above. Everlasting things concern the principles and axioms of the sciences which are changeless truths. These changeless truths in the memory come from a changeless light present in itself.

From the intellect we come to see an image of God. The intellectual activity consists in understanding terms, propositions, and inferences. With terms we go from definitions of the least general to the more general. We must understand the highest and most general term to know the less general. Thus, we must know being per se to know the definition of a particular substance. We must have some knowledge of Absolute Being. How can we know specific being is defective and incomplete unless we have a knowledge of a Being free from all defect? With propositions we must have certainty that they are true to comprehend their meaning. The mind itself is changeable and yet we know truth is changeless. Created light is subject to change. Thus, the intellect must be informed from some other light which is unchangeable. This light comes from God. With inferences the conclusion follows necessarily from the premises. The necessity of the inference does not come from the contingent existence of a thing in matter or a fictional existence in the mind. Therefore it must come from an exemplarity in the Eternal Art concerning the relational character of things. So we see the intellect must have some connection or joining with eternal Truth itself in order to understand any truth with certitude.

The Will consists in counsel, judgement, and desire. From each of these aspects of the Will St. Bonaventure will show how they are enlightened or are stamped with the image of God. Counsel involves inquiring into that which is better. To know that which is better we must have an idea of that which is the best. This notion of the highest good must of necessity be impressed upon those who give counsel. Again with judgement we see an impression of the Divine. Our judgements are made according to law. We must be certain the law is right to use it. Our mind judges itself and yet does not judge the law. Therefore, the law is above our mind and is stamped on it. Desire is concerned with what moves it most. The object loved most moves it most. We love happiness most. Happiness is only attained when we have reached our best and highest end. Therefore, we seek the highest Good. In summary, all three faculties of the soul lead to God and are enlightened by Him. St. Bonaventure says, ". . .how close the soul is to God, and how through their activity, the memory leads us to eternity, the intelligence to Truth, and the elective faculty to the highest Good".7 We see the soul incapable of operation without access to an illumination from above. He says we "...have certain and infallible laws as lights and beacons shining down into our mind from the eternal law. And thus our mind…can be guided through itself to contemplate that eternal Light".8

Finally, we arrive at the light which shines upon our mind from above. St. Bonaventure says, "This is the light of Eternal Truth, since ‘our very mind is formed immediately by Truth Itself’".9 We see the direct influence of St. Augustine in this statement as he is quoted concerning his doctrine of the illumination of the mind from above to see Eternal Truths. St. Bonaventure goes on to elaborate on two ways of contemplating the invisible and eternal things of God. In one method the soul fixes its gaze on Being Itself. When we consider Being Itself, we are looking at "...the principal root of the vision of the essential attributes of God. as well as the name through which the others become known" 10 We discover the essential attributes of God through the corresponding opposites which are inseparable from them. For example, non-being is the privation of being. It cannot come into our intellect except through being. We see that one necessarily implies the other. Therefore, "that Being which is called pure being and simple being

and absolute being is the first being, the eternal, the most simple, the most actual, the most perfect, and the supremely one".11 St. Bonaventure says "these, things are so certain that their opposites cannot be thought of by one who really understands being itself".12 If we consider these things "in the pure simplicity of your mind, you will be somewhat suffused by the illumination of Eternal Light".13

The second method fixes the souls gaze on the Good Itself. Most of St. Bonaventure’s discussion is centered on the Trinity. From a philosophical point of view, he does borrow an argument similar to the Ontological Argument for God’s existence of St. Anselm. He says, "…the highest good is unqualifiedly that in comparison with which a greater cannot be thought. And this good is such that it cannot rightly be thought of as non-existing, since to be is absolutely better than not to be".14 St. Bonaventure says that good is claimed to be self-diffusive. Therefore, the highest good is the most self-diffusive. He goes from here to discuss the proper attributes of the Divine Persons. The most perfect illumination of the mind occurs at this stage when we behold "‘Christ the Son of God, Who is by nature the image of the invisible God’".15

In conclusion, we have seen how St. Bonaventure goes through the illuminations of God which are contained outside of us, within us, and above us. We are illuminated outside of us by vestiges of God when we consider the potential excellence of things, the habitual course of things, and the actual existence of things. God also shines forth in visible Creation in creatures themselves. We abstract from the sense image that which is purely spiritual. So the visible leads to the invisible things of God. Within ourselves or our soul we find the Memory, Intellect, and Will stamped with and leading to illuminations from above. With the Memory’s capability of remembering past, present, and future it becomes an image of eternity where all is present. The Intellect must be enlightened by eternal Truth to have certitude. The Will is stamped with and seeks the highest Good. Finally, we come to the illumination from above when we contemplate the invisible and eternal things of God. When we look at Being Itself, we discover essential attributes of God of which the opposites could not be conceived of or separated from Being Itself such~as non—beinq. Another way of contemplating the light above us is through fixing our gaze on the Good Itself. We see as the basis for all these illuminations St. Augustine’s influence concerning a Divine Light which illumines the mind to perceive Eternal Truths. Also, Sacred Scripture has a great influence on St. Bonaventure’s development of all aspects of Creation containing or pointing to some aspect or likeness of God. Of course, the height of illumination for the mind is contemplating the Son of God Who joined the Divine Nature with human nature. He is the doorway for us to pass through to gain access to the "Father of Lights" which St. Bonaventure refers to in beginning his treatise.


  1. St. Bonaventure, Itinerarium mentis in Deum. Edited by Philotheus Boehner, O.F.M., Ph.D. (New York: Saint Bonaventure University, 1956), p. 81.
  2. Ibid.
  3. Ibid., p.45.
  4. Ibid., p.59.
  5. Ibid., p.61.
  6. Ibid.
  7. Ibid., p. 69.
  8. Ibid., p. 71.
  9. Ibid., p. 81.
  10. Ibid., p. 89.
  11. Ibid., p. 85.
  12. Ibid.
  13. Ibid.
  14. Ibid., p. 89.
  15. Ibid., p. 95.


Bettoni, Efrem, Saint Bonaventure. Translated by Anqelus Gambatese, O.F.M., Indiana, University of Notre Dame Press, 1964.

St. Bonaventure, Itinerarium mentis in Deum. Translated by Philotheus Boehner, O.F.M., Ph.D., New York, Saint Bonaventure University, 1956.

St. Bonaventure, Vol. I of The Works of St. Bonaventure. Translated by Jose de Vinck, New Jersey, St. Anthony Guild Press, 1960.

St. Bonaventure, Vol. III of The Works of St. Bonaventure. Translated by Jose de Vinck, New Jersey, St. Anthony Guild Press, 1960.

Bougerol, J. Guy, O.F.M., Introduction to the Works of St. Bonaventure. Translated by Jose de Vinck, New Jersey, St. Anthony Guild Press, 1964.

Gilson, Eteinne, The Philosophy of St. Bonaventure. Translated by Dom Illtyd Trethowan, New Jersey, St. Anthony Guild Press, 1965.

Quinn, John Francis, The Historical Constitution of St. Bonaventure’s Philosophy, Canada, Pontifical Institute of Mediaeval Studies, 1973.

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