[Heidegger] assimilates certain basic determinations of the Aristotelian concept of truth
and restores their validity through an ontologizing reconfiguration.
In broad outlines this topology can be summarized in the following manner:
1) beings themselves [das Seiende selbst] are primarily true in the sense of their being-manifest, being-uncovered, being-unconcealed.
Here Heidegger re-establishes the Aristotelian determination of ὃν ὡς ἀληθές, being as true.
2) In addition, then, Dasein, human life, is true in the sense of its being-uncovering,
that is, on the basis of its comportement that uncovers beings.
Here Heidegger assimilates the Aristotelian determination of the ψυχή ὡς ἀληθεύειν,
the soul of being-in-truth.
Furthermore, Heidegger believes he can with some justification draw from Aristotle,
especially from the 6th Book of the Nicomachean Ethics,
a complete phenomenology of the uncovering comportments, of being-in-the-truth,
belonging to human life.
These comportments can be detailed as follows.
The human ψυχή, Dasein, can in the first place be uncovering through its specific capacity
of combining that belongs to λόγος; this occurs in the five ways of being-in-truth,
of the ἀληθεύειν of ψυχή that are named in Nicomachean Ethics Ζ:
τέχνη, technique; ἐπιστήμη, science; φρόνησις, prudence; σοφια, wisdom; νοῦς, reason.
But the human ψυχή, Dasein, can also be "intuitively" uncovering in immediate apprehension;
it can be this in αἲσθησις, sensation (which is related to its ἴδιον, its proper object,
and is thus αει ἀληθής, always true) or in νόησίς, reason
(which apprehends its object through as it were a θιγγανειν, θιγειν, a touching,
and this cannot be false, but rather only actualized [vollzogen] or, on the other hand, absent in αγνοειν, ignorance).
The above-named combining comportments are grounded in the immediately uncovering ones.
3) Finally, what is true is the explicit form of λόγος, namely, the λόγος ἀποφαντικός,
the predicative assertion in its two forms of κατάφασις and ἀπόφασις, affirmation and denial.
The being-true of the assertion is, however,
a derivative mode of the originary happening of truth in which it is grounded.
By means of this ontologizing reconstruction of Aristotle's theory of truth,
Heidegger disengages the understanding of the phenomenon of truth from the structure
of the assertion and opens up the ontological horizon in which he unfolds the problem of beings in the sense of the true.
It is in the context of the analysis of this basic meaning of beings in the sense of the true
that Heidegger devotes himself in the twenties to determining the basic ontological structure of human life,
Dasein, the ψυχή, and indeed in its specific character of being-uncovering.
It is thus in the context of the typical phenomenological question of the basic constitution of "subjectivity"
the Heidegger interprets the Aristotelian determination of ψυχή as ἀληθεύειν,
being-in-truth, and it is with this combination of a phenomenological mode of access and Aristotelian components
that he gets the existential analysis of Being and Time going.