James Spiegel

“This means that we can have no metaphysical knowledge, no knowledge of reality beyond our immediate, personal experience. The implications of Hume's empiricism are profound. It is not just the existence of material objects and causal relations that are called into question. Since we have no sensory impressions of God, and neither can we infer God's existence through causal reasoning based on things we have experienced, God is unknowable. Since we have no impressions of things like “wrongness” or “rightness,” but only subjective feelings about actions that people perform, we cannot know absolute moral truths. Since I have no impression of other minds, I cannot know that other people exist. Since I have no impression of a “self” or “soul,” but only impressions of internal feelings and images, I cannot even know that I exist.”
― James Spiegel, The Love of Wisdom: A Christian Introduction to Philosophy