**Non-Chacedonians belong to the Alexandrian School and are miaphysites.
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Miaphysitism: Christ in one united nature (of two natures: Divinity and Humanity) in one person, his divinity united with his humanity in a real and perfect union without mingling, without confusion, without alteration, without division, without separation.
The Catholic Saint, Pope Cyril of Alexandria, taught miaphysitism.
In respect of the elements from which is the one and only Son and Lord Jesus Christ, as we accept them in thought, we say that two natures have been united, but after the union, when the division into two has now been removed, we believe that the nature of the Son is one. - St Cyril of Alexandria, Select Letters, 48
We confess that He is Son of God and God according to the Spirit, Son of Man according to the flesh, not Two Natures to that One Son, One [Nature] worshipped the other unworshipped, but One Nature of God the Word Incarnate, worshipped with His flesh with One worship: nor Two Sons, One, Very Son of God and worshipped, the other the man out of Mary not worshipped, made by grace son of God just as men too are. - St Cyril of Alexandria, Against Theodore
Chacedonians belong to the Antiochian School and are dyophysites.
Dyophysitism: Christ in two natures (Divinity and Humanity) united in one person, his divinity united with his humanity in a real and perfect union without mingling, without confusion, without alteration, without division, without separation.
The Fathers of the Council of Chalcedon taught dyophysitism.
This one and the same Jesus Christ, the only-begotten Son [of God] must be confessed to be in two natures, unconfusedly, immutably, indivisibly, inseparably [united], and that without the distinction of natures being taken away by such union, but rather the peculiar property of each nature being preserved and being united in one Person and subsistence, not separated or divided into two persons, but one and the same Son and only-begotten, God the Word, our Lord Jesus Christ, as the Prophets of old time have spoken concerning him, and as the Lord Jesus Christ hath taught us, and as the Creed of the Fathers hath delivered to us. - The Council of Chalcedon, Definition of Faith
A Catholic (Chacedonian) and Syriac Orthodox (Non-Chacedonian) Joint Statement Piece:
Progress has already been made and Pope Paul Vl and the Patriarch Mar Ignatius Jacob III are in agreement that there is no difference in the faith they profess concerning the mystery of the Word of God made flesh and become really man, even if over the centuries difficulties have arisen out of the different theological expressions by which this faith was expressed. They therefore encourage the clergy and faithful of their Churches to even greater endeavours at removing the obstacles which still prevent complete communion among them. This should be done with love, with openness to the promptings of the Holy Spirit, and with mutual respect for each other and each other’s Church. They particularly exhort the scholars of their Churches, and of all Christian communities, to penetrate more deeply into the mystery of Christ with humility and fidelity to the Apostolic traditions so that the fruits of their reflections may help the Church in her service to the world which the Incarnate Son of God has redeemed. - Singed Statement by Syriac Patriarch Mar Ignatius Jacob III of Antioch and Pope Paul Vl of Rome
It doesn’t matter if you understand the Incarnation better in miaphysite terms or dyophysite terms. As long as you accept that both are different orthodox understandings of the same teaching of the doctrine of the Incarnation, it really doesn’t matter where you stand.
Here are the heretical views that are from one extreme to another:
Eutychianism: Christ in one nature that is a mixture and confusion of Divinity and Humanity in one person. He is not fully God. He is not fully man. He is a mixture of God and man in one person.
Nestorianism: Christ in two natures that have come to each other. One is Divine and is worshipped and the other one is a man and is unworshipped. The two persons are one in dignity.