"Our tradition of political thought had its definite beginning in the teachings of Plato and Aristotle. I believe it came to a no less definite end in the theories of Karl Marx"

In this quote, Hannah Arendt is reflecting on the historical trajectory of Western political idea, presuming that it has a distinct beginning and end marked by the approaches of specific thinkers. She identifies Plato and Aristotle as the fundamental figures whose ideas inaugurated the custom, underscoring their significant contributions to concepts like political order, justice, and virtue. Their works established sustaining frameworks for comprehending political life and governance, affecting numerous thinkers and political systems over the centuries.

Arendt's referral to Karl Marx as the point at which this tradition pertains to a "no less definite end" suggests a transformative shift in political idea. Marx's theories, particularly his critique of industrialism and his ideas on class struggle and historical materialism, represent a radical departure from classical and much more modern analyses of politics by providing thorough analyses of economic systems and their ramifications for social structures. Marx introduced an important viewpoint that challenged the fundamental presumptions of previous political approaches, especially regarding the roles of economics, class, and power characteristics in forming political truth.

This juxtaposition highlights a shift from classical philosophical interest in perfect states and ethical governance to Marx's focus on material conditions and social modification. Arendt might be recommending that Marx's work marked the conclusion of political thought as it was previously known, presenting a paradigm shift that went beyond the philosophical borders set by thinkers like Plato and Aristotle. By framing Marx as an endpoint, Arendt recognizes the enduring impact and advanced nature of his ideas on subsequent political discourse and action, which continue to resonate in modern arguments.

This interpretation does not suggest that political idea or viewpoint disappeared after Marx; rather, it emphasizes that his contributions basically altered the trajectory and focus of Western political theory, incorporating a socio-economic measurement that had formerly been ignored. The quote encapsulates Arendt's view on how the development of political thought shows broader changes in human understanding and societal structures.