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Work #1753

Fragments and Testimonia

Protagoras of Abdera
c. 5th century BCE (fragments preserved in Plato, Sextus Empiricus, Diogenes Laertius) · Ancient Greek
Fragments and testimonia (reconstructed) · Sophistic philosophy / Presocratic epistemology

Man is the measure of all things — the founding statement of Western relativism and the first professional educator of Greece

Attribute Fingerprint

Rows where works disagree are highlighted in gold. The full ontology grid is shown.

Attribute Fragments and Testimonia
Time · Extent Infinite
Time · Ontological Status Relational
Time · Grain Continuous
Time · Freedom Non-Deterministic
Time · Traversability Linear
Time · Dimensionality One
Time · Direction Uni-directional
Space · Extent Infinite
Space · Ontological Status Relational
Space · Curvature Flat
Space · Dimensionality Three
Space · Locality Local
Matter · Extent Infinite
Matter · Ontological Status Relational
Matter · Conservation Variable
Matter · Dimensionality Three
Matter · Locality Local
Observer · Time Instance Single
Observer · Space Instance Single
Observer · Knowledge Extent Partial
Observer · Knowledge Retainment Immediate
Observer · Physicality Embodied
Observer · Agency Active
Observer · Number Plural
Observer · Metaphysical Agency None
Observer · Moral Authority Experience
Observer · Theological Method
Energy · Extent Infinite
Energy · Ontological Status Relational
Energy · Conservation Variable
Energy · Dispersibility Irreversible
Information · Ontological Status Relational
Information · Cosmic Conservation Non-conserved
Information · Personal Conservation Non-conserved
Information · Granularity Continuous

Dimension-by-Dimension Evidence

What each work's passages reveal about its stance on each of the six dimensions.

Time

Fragments and Testimonia

Time in the man-measure framework is relational — it exists as experienced by the human observer, not as an independent substance. What matters is the human present, not a cosmic temporal order.

Space

Fragments and Testimonia

Space is similarly relational — the relevant spatial frame is the human perceiver's situation, not an absolute container.

Matter

Fragments and Testimonia

If man is the measure, then the properties of matter are as they appear to the perceiver. The wind is cold to one who shivers and warm to one who does not (Plato, Theaetetus 152b).

Observer

Fragments and Testimonia

The observer is central — Protagoras is the first philosopher to make the observer the constitutive element of knowledge. The observer is embodied, active, plural (different observers yield different truths), and empirical.

Energy

Fragments and Testimonia

Energy is relational — what counts as forceful or weak depends on the human being who experiences it. There is no absolute energetic standard.

Information

Fragments and Testimonia

Information is not conserved in any absolute sense — it is relative to the knower. What is true for one may not be true for another. Knowledge is situation-dependent and ephemeral.

Internal Tensions

Where each work's argument pulls against itself.

Fragments and Testimonia

The central tension is the self-refutation problem: if man is the measure of all things, is the man-measure doctrine itself only relatively true? Plato presses this objection in the Theaetetus, and it remains the standard criticism. A second tension is between Protagoras the epistemological relativist and Protagoras the practical educator — he charged large fees to teach people to argue better, which implies that some arguments are better than others, undermining radical relativism.