In my thesis, I explore the role of knowledge in intentional action within the scope of early Greek philosophy and medicine. I investigate how knowledge influences both the intention behind an action and its successful delivery. Specifically, I look at the works of authors who discuss a particular type of knowledge that I refer to as 'knowledge of causes', a knowledge which offers explanation in terms of causes. I am particularly interested in understanding how a knowledge of causes which is holistic, general, and separable from action, is employed to justify or inform intentional actions.

My research draws from various sources, including Heraclitus, who presents an implicit theory of action in his account of 'logos'. This theory proposes a framework in which the success of decision-making including ethical and political decision-making hinges upon a comprehensive grasp of logos. The stronger a grasp of logos the more unified larger decision-making bodies become, the firmer a plan may be grounded in an understanding of contextualising information, and the more control an agent will have over the delivery of their plan.

Additionally, I examine the Hippocratic treatise On Regimen, who presents a holistic knowledge of causes represented by a reductive physical explanation in terms of the powers of fire and water. This framework supports medical decision-making by providing a comprehensive understanding of both bodily and cosmic systems in causal terms. Furthermore, it recognises the significance of dream diagnosis as a reliable source of information about patients, thereby enhancing its explanatory potential.

Finally, I delve into the perspectives of Democritus, for whom holistic knowledge of causes serves as fundamental ethical principles expressed through guiding maxims for ethical decision-making. Agents must grasp the underlying fundamental ethical principles within these maxims to effectively apply them to their own circumstances. Failure to do so results in blindness towards the right information required for action, the wrong desires and ultimately, unsuccessful ethical action.