“The problem is one of opposition between subjective and objective points of view. There is a tendency to seek an objective account of everything before admitting its reality. But often what appears to a more subjective point of view cannot be accounted for in this way. So either the objective conception of the world is incomplete, or the subjective involves illusions that should be rejected.”

Heinz von Foerster cited in: Bernhard Poerksen (2004). The Certainty of Uncertainty: Dialogues Introducing Constructivism. p.3
2000s and attributed from posthumous publications

Source: Psychology and the Human Dilemma (1967), p. 20
Context: I have described the human dilemma as the capacity of man to view himself as object and as subject. My point is that both are necessary — necessary for psychological science, for effective therapy, and for meaningful living. I am also proposing that in the dialectical process between these two poles lies the development, and the deepening and widening, of human consciousness. The error on both sides — for which I have used Skinner and the pre-paradox Rogers as examples — is the assumption that one can avoid the dilemma by taking one of its poles. It is not simply that man must learn to live with the paradox — the human being has always lived in this paradox or dilemma, from the time that he first became aware of the fact that he was the one who would die and coined a word for his own death. Illness, limitations of all sorts, and every aspect of our biological state we have indicated are aspects of the deterministic side of the dilemma — man is like the grass of the field, it withereth. The awareness of this, and the acting on this awareness, is the genius of man the subject. But we must also take the implications of this dilemma into our psychological theory. Between the two horns of this dilemma, man has developed symbols, art, language, and the kind of science which is always expanding in its own presuppositions. The courageous living within this dilemma, I believe, is the source of human creativity.

Source: Middlemarch

Source: The Social Construction of Reality, 1966, p. 163

Memoirs of Aga Khan: World Enough & Time (1954)
Context: Life in the ultimate analysis has taught me one enduring lesson. The subject should always disappear in the object. In our ordinary affections one for another, in our daily work with hand or brain, we most of us discover soon enough that any lasting satisfaction, any contentment that we can achieve, is the result of forgetting self, or merging subject with object in a harmony that is of body, mind and spirit. And in the highest realms of consciousness all who believe in a Higher Being are liberated from all the clogging and hampering bonds of the subjective self in prayer, in rapt meditation upon and in the face of the glorious radiance of Eternity, in which all temporal and earthly consciousness is swallowed up and itself becomes the eternal.

Quaestiones subtilissimae de metaphysicam Aristotelis, as translated in: William A. Frank, Allan Bernard Wolter (1995) Duns Scotus, metaphysician. p. 20-21

On Contradiction (1937)
Original: (zh-CN) 人的概念的每一差异，都应把它看作是客观矛盾的反映。客观矛盾反映入主观的思想，组成了概念的矛盾运动，推动了思想的发展，不断地解决了人们的思想问题。

Living Systems: Basic Concepts (1969)