Final answer:
John Locke, George Berkeley, David Hume, and David Hartley are considered empiricists because they believed knowledge comes from sensory experiences.
Step-by-step explanation:
John Locke, George Berkeley, David Hume, and David Hartley are at heart B. Empiricists. These philosophers are associated with the philosophical view known as empiricism, which emphasizes that knowledge comes from sensory experience and that we begin with a blank slate, or tabula rasa.
While some, like Berkeley, leaned towards idealism, advocating that only minds and ideas truly exist, they were still anchored in the empiricist tradition which suggests that all knowledge is derived from our sensory experiences.
John Locke argued that at birth, our minds are a blank slate, and all knowledge is a result of experience. Berkeley took this further and integrated his belief in God to suggest that all existence is dependent on being perceived by some mind, ideally God's.
Hume, while also aligned with empiricism, introduced a skeptical view by doubting our ability to know much with certainty beyond our immediate sensory experiences. David Hartley contributed to the development of associationist psychology, also grounded in empiricist thought.