So this term has had a lot of impact religiously and philosophically, yet I still do not understand why logos as discourse or word was taken by Stoics and Platonists as some divine principle and by scientists as logic or -logy, like biology, geology, etc. What does that have to do? I mean you can make sense of the latter sense as a discourse of life, the discourse of the earth, the list of things that can be said about life or earth. But why logic, what does that have to do with it? What does word have to do with a divine intermediary that builds or animates the world? Can anyone explain how the senses of the word evolve? Some references for this transition? why logos as discourse or word was taken by Stoics and Platonists as some divine principle and by scientists as logic or -logy, like biology, geology, etc. What does that have to do? You have it backward. The original sense of logos is that of the principle which put order into the original chaos. It was a way of explaining the fact that there was order in the world. The Greek λόγος (lógos) is related to Ancient Greek λέγω (légō), which derives from the Proto-Indo-European root leǵ-, which meant I put in order, arrange, gather, choose, count, reckon, discern, say, speak. Christianity came later to reclaimed the idea for itself, recycling it as the creative word of God. The idea of logos also gave rise to the two complementary ideas of natural laws and logic: natural laws as what explains the order of the world, and logic as what puts order in the human mind. I don't know if what you are referring to is a historical transition. It looks more like several meanings for the same word, which is common. Logos in the theological sense, with a uppercase L, means that God designed the universe to function according to laws, laws that He chose and edicted. So in this view, the act of creating the universe was a speech act by God. He wrote the code. Like in Genesis, Hesaid: let X be, and X was. Or like in John: In the beginning was the Word... Okay, so what you are asking after isconceptual analysisof a term used in philosophy. Linguists would better suited to explain to you the science of how written and spoken words acquire meanings and then change over time. There's a whole sub-discipline related to etymology calledhistorical linguistics. Without getting into contemporary theories on it, such as those offered bycognitive semantics, my preferred theory, let's just say that words are coined and then follow rules of association which may alter the morphology and semantics. Some insight can be found in the WP article on'logos': logos (UK: /ˈloʊɡɒs, ˈlɒɡɒs/, US: /ˈloʊɡoʊs/; Ancient Greek: λόγος, romanized: lógos, lit. 'word, discourse, or reason') is a term used in Western philosophy, psychology and rhetoric; it connotes an appeal to rational discourse that relies on inductive and deductive reasoning. Aristotle first systemised the usage of the word, making it one of the three principles of rhetoric alongside ethos and pathos. So, it comes from Ancient Greek probably with the literal meaning of 'word' and the figurative meanings 'discourse' and 'reason'. You can see the obvious connection. Discourse which generally entails reason, uses words. Thus our 'dialogue' is 'discourse between two' and 'logic' is 'the form reason takes'. Biology literally translated is 'life-words', 'life-discourse', or 'life-logic' all three of which are constructions much like our own Anglo-Saxonkennings. Now, once a word is in circulation the meaning can change either unintentionally by usage or intentionally by stipulation. Philosophers routine coinneologismsand repurpose written and spoken words asreference with new meanings. This is called astipulative definition. This is calledsemantic shiftand can be severe enough that meanings may become unrelated or opposite to original usage. It is common in philosophy because philosophers attempt to create a moreexpressivelanguage. From WP: Semantic change (also semantic shift, semantic progression, semantic development, or semantic drift) is a form of language change regarding the evolution of word usage—usually to the point that the modern meaning is radically different from the original usage. You ask: But why logic, what does that have to do with it? What does word have to do with a divine intermediary that builds or animates the world? Logic is a property that inheres to language (coming from the Latin tongue:D) and is made of words. And why might Plato have associated it with divinity? Well, consider that words were considered real by Plato under his theory of Forms which were close to the divine, particularly the Form of the Good.