In brief: No — and this point decides the understanding of the whole method. The moments do not stand over against each other as two fixed quantities between which mediation then takes place. Each is only what it is through the other — and passes over into the other on its own account. Whoever thinks them as a pair has the understanding and not dialectic.
The three sides of the logical
In Encyclopaedia § 79 Hegel distinguishes three sides which are not three parts but moments of every concept: the understanding side, which holds fast to the fixed determination and its difference from others; the dialectical or negatively rational, in which these determinations sublate themselves; the speculative or positively rational, which grasps the unity of the determinations in their opposition.
Dualism accordingly belongs to the first side. It is not false — without it one would arrive at no determinacy — but it is not the last word. Encyclopaedia § 81 says that the finite is sublated „not merely limited from outside, but through its own nature“, and passes „through itself into its opposite“.
Why it is not a standing-opposite
An opposition in Hegel’s sense is not a juxtaposition of two things. Being and nothing do not stand side by side like two quantities, between which becoming then mediates: pure being, precisely because it has no determination whatever, is not to be distinguished from nothing. The transition lies in the determination itself, not between two determinations.
The result is therefore not a mixture of the two either. It is the determinate negation:
Since what results, the negation, is determinate negation, it has a content. It is a new concept, but a higher, richer concept than the preceding one.
Science of Logic I, Introduction
Hegel’s own image for it is not the balance but the plant:
The bud disappears in the bursting forth of the blossom, and one might say that the former is refuted by the latter […]. But their fluid nature makes them at the same time moments of an organic unity, in which they not only do not conflict, but in which each is as necessary as the other.
Phenomenology of Spirit, Preface
An example from the Groundlines
Right and wrong are not a pair of opposites between which punishment mediates. § 82 determines wrong as the semblance of right against right — it arises out of right, not alongside it. And § 99 says that the violation has „no positive existence“ except in the particular will of the criminal. Wrong is accordingly no second principle but a shape of right that contradicts itself. That is why punishment can sublate it without anything third being added.
Likewise abstract right and morality do not stand over against each other as outer and inner, to be set off against each other in ethical life. Morality issues from the failure of abstract right (§ 104), and ethical life from the failure of morality on its own indeterminacy (§ 141).
Where the misunderstanding comes from
From the textbook formula thesis – antithesis – synthesis. It presupposes precisely the picture Hegel disputes: two finished propositions and a third that balances them. The formula does not come from him; he uses it in reporting on Kant and rejects schematic triads as lifeless. Whoever brings it along will find nothing in Hegel that fits it — and will wrongly conclude that there is nothing there.
Sources. Encyclopaedia (1830) §§ 79–82 with Additions. – Science of Logic I, Introduction and First Chapter; Logic II, First Section (opposition, contradiction). – Phenomenology of Spirit, Preface. – Groundlines § 31 Remark, § 82, § 99, § 104, § 141. – Literature. Gustav E. Mueller, „The Hegel Legend of ‚Thesis–Antithesis–Synthesis‘“, Journal of the History of Ideas 19 (1958); Michael Theunissen, Sein und Schein, Frankfurt a. M. 1978. – In the glossary: contradiction, determinate negation, understanding, the speculative.