I found this way of introducing Socrates' daimonion, well, weird:
I don't mean that 'the English of earlier centuries' must mean, in the context, the English who lived before Plato. I mean, rather, that 'weird', derived from Wyrd, the Norse personification of Fate, is not at all like Socrates' daimonion. Moreover, why introduce the term, misleadingly, as if it functions primarily as an adjective (a weird 'sign' or 'voice')? Doesn't to daimonion in Plato typically mean not 'that which is divine' but rather 'that divine agent' (as the author can't help but say, in the last sentence quoted). But see the full review here.
The Socrates depicted in Plato's dialogues spoke of a daimonion signal that came to him. That word daimonion is an adjective meaning "daimôn-ish" -- divine, or maybe what the English of earlier centuries called "weird."
Anyway the sign came as some kind of voice and Socrates claimed to have heard it since childhood. It was apotreptic rather than protreptic, never commanding Socrates to act some way but only making sure he heard the discouraging word whenever he chanced to embark on a harmful action (Apology 31d).
Xenophon's Socrates heard a somewhat different voice, one that did not hesitate to endorse one action over another. Plato consistently presents an inhibiting divine agent.