A few days ago I heard a professor (though not a classicist) argue that the word ‘theory’ and ‘theos’ were cognates. My initial reaction was that he was probably wrong and that the two words were at best false friends, but now, when I look at the etymology section of the Wiktionary entry for θεωρός, it reads as follows: “From θέᾱ (théā, “sight”) + ὁράω (horáō, “I see”). Although with partial signification from θεός (theós, “god”).” So it apepars that words such as θεωρέω and θεωρός are indeed cogante with θεός, which I find surprising. It seems to me difficult to establish a sematic relation between watching and God.
The non-classicist professor is wrong. “Theory” is cognate with θέᾱ, not with θεός.
While MWH is right, the non-Classicist professor isn’t exactly making it up either:
•ETYM Properly “who watches a show”, *θεᾱ-(ϝ)ορός, *θεη-(ϝ)ορός > θε(ε)ωρός with quantitative metathesis and hyphaeresis; also, θεορός > θευρός, probably after -ορος (as in ἔφορος). See Buck 1953: 443f. and Szemerényi Glotta 33 (1954): 2502. Koller Glotta 36 (1958): 273ff. connects θεωρός with θεός, which is implausible; see the objections in DELG.
Beekes, R. (2010). A. Lubotsky (Ed.), Etymological Dictionary of Greek (Vol. 1 & 2, p. 545). Leiden; Boston: Brill.
My favorite example of this came in a logic lecture I heard years ago. The teacher claimed that the “modus ponens” form of argument was from the Latin for “powerful method”, “and”, he said with gusto, “it is a POWERFUL METHOD indeed!” You know someone’s Latin is weak when they can’t tell the difference between “methodus potens” and “modus ponens”. It was embarrassing and amusing.
You are right, the non-classicist professor, as well as Wikipedia, are wrong, and the real classicist professor is pulling your leg.
Read the entries in LSJ:
θεωρ-ία , Ion. -ίη, Dor. θεα_ρία (v. infr.), Boeot. θιαωρία Ἐφ.Ἀρχ.1892.34: ἡ:—
A.sending of θεωροί or state-ambassadors to the oracles or games, or, collectively, the θεωροί themselves, embassy, mission, “θεωρίαν ἀπάγειν εἰς Δῆλον” Pl.Phd.58b: pl., opp. στρατεῖαι, Id.R.556c; ἄγειν τῷ Διὶ τῷ Νεμείῳ τὴν κοινὴν ὑπὲρ τῆς πόλεως θ. D.21.115, cf. X.Mem.4.8.2, Decr.Byz. ap. D.18.91 (θεα_ρία), Plb.28.19.4.
2. office of θεωρός, discharge of that office, τῆς Ὀλυμπίαζε θ. Th.6.16, cf. Isoc.19.10, etc.
II. being a spectator at the theatre or games, S.OT1491; “οὔτ᾽ ἐπὶ θεωρίαν πώποτε ἐκ τῆς πόλεως ἐξῆλθες” Pl.Cri.52b; personified in Ar.Pax523,al.
III. viewing, beholding, θεωρίης εἵνεκεν ἐκδημεῖν to go abroad to see the world, Hdt.1.30; κατὰ θεωρίης πρόφασιν ib.29; “ἐκπέμπειν τινὰ κατ᾽ ἐμπορίαν καὶ κατὰ θεωρίαν” Isoc.17.4, cf. Arist.Ath.11.1, Th.6.24; pilgrimage, E.Ba.1047.
2. of the mind, contemplation, consideration, Pl.Phlb.38b: pl., θεῖαι θ. Id.R.517d: c. gen., παντὸς μὲν χρόνου πάσης δὲ οὐσίας ib.486a; ἡ τῶν ἀρχῶν, ἡ τῶν ὅλων θ., Epicur.Ep.2p.55U., Phld.Rh.1.288S.; “θ. ποιεῖσθαι περί τινος” Arist.Metaph.989b25; ἡ περὶ φύσεως θ. Epicur.Ep.1p.3U., etc.: pl., τὰς σαθρὰς αὐτοῦ θ. Demetr. Lac.Herc.124.12.
b. theory, speculation, opp. practice, Plb. 1.5.3; ἡ περὶ τὰ στρατόπεδα θ. Id.6.42.6; αἱ νυκτεριναὶ καὶ ἡμεριναὶ θ. theoretic reckoning of night and day, Id.9.14.6; ἡ μαθηματικὴ θ. Plu. Rom.12.
3. Pass., sight, spectacle, A.Pr.802, etc.; esp. public spectacle at the theatre or games, Ar.V.1005, X.Hier.1.12; ἡ τοῦ Διονύσου θ. the Dionysia, Pl.Lg.650a.
4. Rhet., explanatory preface to a μελέτη, Chor. in Hermes 17.208, etc.: so in Philos., continuous exposition, Olymp.in Mete.18.30, al.
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θεάομαι , Ep. and Ion. θηέομαι (v. infr.), Dor. θα_έομαι , Θάομαι (qq. v.), imper.
A.“θεῶ” Ar.Ach.262; opt. θηοῖο (for Att. θεῷο) Il.24.418; part. “θηεύμενος” Hdt.7.146: Ion. impf. ἐθηεῖτο, ἐθηεῦντο, Id.1.10, 3.136; Ep. “θηεῖτο” Od.5.75, etc., “θηεῦντο” Il.7.444, al., “ἐθηεύμεσθα” Od.9.218, “ἐθεῆτο” Hp.Nat.Puer.13, θηέσκετο Poet. ap. Parth.21.2: fut. θεάσομαι [α_], Ion. -ήσομαι: aor. ἐθεα_σάμην, Ep. opt. θηήσαιο, θηήσαιτο, Od.17.315, 5.74; 3pl. “ἐθηήσαντο” Euph.51.15; Ion. inf. θεήσασθαι (v.l. θεάσ-) Hdt.1.8: Att. pf. “τεθέαμαι” X.Cyr.7.5.7: codd. of Hdt. vary betw. θεη- and θηη-: a rare Ion. contr. of θηη- to θη- is found in “θησαίατ᾽” Od.18.191, “θησάμενος” IG12.826:—gaze at, behold, mostly with a sense of wonder, “θηεῦντο μέγα ἔργον” Il.7.444, cf. Od.2.13; “λαοὶ δ᾽ αὖ θηεῦντό τε θάμβησάν τε” Il.23.728, cf. Hdt.1.8,11, etc.; “θ. τὰ καλά” Democr.194; “πάντες ὥσπερ ἄγαλμα ἐθεῶντο αὐτόν” Pl.Chrm. 154c; “θ. ὄμμασι” E.Ion232 (lyr.); “ζητεῖ τὸ κακὸν τεθεᾶσθαι” Ar.Th.797 codd.; ἐθεᾶτο . . τὴν θέσιν τῆς πόλεως . . , ὡς ἔχοι reconnoitred it, Th.5.7; “θ. κύκλῳ τὴν πόλιν” X.Cyr.4.5.7: abs., θεᾷ; do you see? Men.Epit. 564.
2. of the mind, contemplate, “τὸ ἀληθές” Pl.Phd.84b, al.
b. see clearly, “ἵν᾽ ἴδητε καὶ θεάσησθε ὅτι . . ” D.4.3, cf. Pl.Prt.352a; with relat. clause, “ὅση δεινότης ἦν ἐν τῷ Φιλίππῳ θεάσεσθε” D.18.144.
3. view as spectators, esp. in the theatre, Isoc.4.44; οἱ θεώμενοι the spectators, Ar.Ra.2, cf.Nu.518, al. (but also, onlookers, bystanders, Antipho 3.3.7): metaph., θ. τὸν πόλεμον to be spectators of the war, Hdt. 8.116.
4. θ. τὸ στράτευμα to review it, X.Cyr.5.5.1.
II. Act. θεάω , late, Baillet Tombeaux des rois à Thèbes 1080: elsewh. in imper. “θέα” Them.Or.3.44b, Jul.Ep.89b, Hsch.: aor. ἐθεάθην in pass. sense, Ps. -Callisth.2.42, Ev.Marc.16.11, Ap.Ty.Ep.49, Just.Nov.133.3.1: pres. “θεῶνται” Philostr.Her.2.9. > (Orig. prob. θα_ϝ έομαι and θα_ϝάομαι, cf. θαῦ-μα.)
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