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Plate tectonics is a fundamental factor in the sustained habitability of Earth, but its time of onset is unknown, with ages ranging from the Hadaean to Proterozoic eons1-3. Plate motion is a key diagnostic to distinguish between plate and stagnant-lid tectonics, but palaeomagnetic tests have been thwarted because the planet's oldest extant rocks have been metamorphosed and/or deformed4. Herein, we report palaeointensity data from Hadaean-age to Mesoarchaean-age single detrital zircons bearing primary magnetite inclusions from the Barberton Greenstone Belt of South Africa5. These reveal a pattern of palaeointensities from the Eoarchaean (about 3.9 billion years ago (Ga)) to Mesoarchaean (about 3.3 Ga) eras that is nearly identical to that defined by primary magnetizations from the Jack Hills (JH; Western Australia)6,7, further demonstrating the recording fidelity of select detrital zircons. Moreover, palaeofield values are nearly constant between about 3.9 Ga and about 3.4 Ga. This indicates unvarying latitudes, an observation distinct from plate tectonics of the past 600 million years (Myr) but predicted by stagnant-lid convection. If life originated by the Eoarchaean8, and persisted to the occurrence of stromatolites half a billion years later9, it did so when Earth was in a stagnant-lid regime, without plate-tectonics-driven geochemical cycling.

Philosophy of technology (PoT) analyzes the nature of technology, its significance and consequences, and its mediation of human experiences of the world. Classical philosophers of technology describe mechanization as alienating: Technology causes humans to lose their connection with the natural world. Tehno-rationality replaces critical engagement and creativity. Failing to comprehend the essence/nature of Technology, and its consequences, portends disastrous social, political, and economic consequences. Such perspectives, however, neglect individual experiences of technologies. Filling that lacuna, contemporary philosophers of technology challenge the sweeping determinism of their intellectual forerunners and investigate how specific technologies mediate particular human experiences. Their descriptive prowess, however, lacks the normative engagement of classical PoT, and they emphasize micro effects of technologies to the detriment of macro implications. This dissertation describes an 'un-disciplined' philosophy of technology (UPoT) that unites the macro and micro perspectives by providing narratives of human-technology symbiosis and co-development. Un-disciplined philosophers of technology present posthuman and transhuman perspectives that emphasize the symbiotic relationships between humans and technology. Thus, they deny disciplined philosophy's first critical maneuver: define and demarcate. UPoT enables conversations and debate regarding the ontological and moral consequences of imagining humans and technologies as hybrid, co-dependent things. UPoT builds upon environmental and animal rights movements, and postphenomenology, to emphasize pluralist accounts that emphasize the dynamism of human-technology relations. UPoT argues we should imagine technologies as extensions/parts of living things: they do the shaping and are shaped in turn. I argue that such thinking reinforces the habit, already proposed by contemporary PoT, that emerging human-technology relations demand active interpretation and engagement because the relationships constantly change. Thus, we need to imagine a moral theory that best matches the hybrid/connected condition of the present century. Increasing automation in agriculture and surgery, for instance, exemplify technologies mediating human experiences of food and health, thus affecting how we understand and define these categories. Ph. D.