This is the first Volume of an encompassing study of the problem of Reformation and Scholasticism in philosophy, focused on Greek philosophy up to and including Plato. Whereas Plato and Aristotle employed the term dialectic within the context of the human ability to discern or to infer, Dooyeweerd uses it to designate the irreconcilable tension between the two opposing poles of the basic motive of Greek thought. He argues that the kind of dialectic found on the level of ultimate commitments, preferably designated by him as a basic motive or ground motive, not only transcends the realm of logical-analytical thinking, but at the same time also informs and directs it. According to him, the basic motive of matter and form, directing the entire development of Greek philosophy, is broken apart by an inherent dialectic. The only option is to assign primacy either to the matter pole (the initial development of Greek philosophy) or the form pole (since Anaxagoras and culminating in the thought of Socrates, Plato and Aristotle), without being able to obtain a higher synthesis and encompassing both. In this encompassing and penetrating work, Dooyeweerd demonstrates why the historian of philosophy should always aim at understanding each epoch in the history of philosophy in terms of its own deepest motivation and direction-giving ground motive.