Three Dialogues between Hylas and Philonous

The Preface begins with a suggestive rhetorical framing, as Berkeley asserts that his seemingly contrarian philosophy is in fact more closely aligned with common sense than that of his opponents, the materialists:

Though it seems the general opinion of the world, no less than the design of nature and providence, that the end of speculation be practice, or the improvement and regulation of our lives and actions, yet those, who are most addicted to speculative studies, seem as generally of another mind (3).

Here, he posits as a self-evident truth that the purpose of philosophy is to improve people’s lives, and then in a lightly mocking tone he implies that most contemporary philosophers have made it their business instead to confuse people and cast them into doubt. This passage highlights one of the text’s central themes: The Critique of Materialism and the Defense of Idealism. Berkeley’s idealism holds that reality is dependent upon the senses—that nothing exists except in that it is perceived. In his view, this is a natural and practical position to have. By contrast, the people “addicted to speculative studies” are those who assert that there is another kind of reality than what can be determined by sensory input. These would be considered materialists.

Importantly, Berkeley points out that materialism requires its adherents to accept that some aspects of reality fall outside sensory perception. His critique of materialism rests on this premise—that it needlessly obscures the picture of reality by positing the existence of hidden phenomena that the senses cannot directly verify: “It is not enough, that we see and feel, that we taste and smell a thing. Its true nature, its absolute external entity, is still concealed. For, though it be the fiction of our own brain, we have made it inaccessible to all our faculties. Sense is fallacious, reason defective” (3). Berkeley’s central claim about The Nature of Existence and the Role of Perception initially seems to contradict common sense: Our senses tell us that trees and rocks and birds exist outside the boundaries of ourselves and remain present even when we are not looking at them, but Berkeley argues that the existence of these objects depends on our perception. By opening in the way he does—highlighting the confusions that arise from materialism—he implies that his own immaterialist view is in fact the simplest and most sensible.

The theme of The Theological Implications of Idealism also emerges in the Preface. Berkeley sees his argument against materialism as simultaneously an argument for existence of God and the immortality of the soul. Berkeley writes, “If the principles, which I here endeavor to propagate, are admitted for true; the consequences which, I think, evidently flow from thence, are, that atheism and scepticism will be utterly destroyed” (4). As a clergyman and a person of devout faith, he sees materialism as a pernicious force, harming its adherents by leading them to doubt the existence of God. As an Enlightenment philosopher, he understands that in order to make a convincing argument, he must rely on reason and logic. He states:

As it was my intention to convince sceptics and infidels by reason, so it has been my endeavor strictly to observe the most rigid laws of reasoning. And, to an impartial reader, I hope, it will be manifest, that the sublime notion of a God, and the comfortable expectation of immortality, do naturally arise from a close and methodical application of thought (4-6).

His argument in favor of God, therefore, will not be without logic. Instead, it will employ the kind of logic that will make the men of science and philosophy (with whom he is arguing) have no choice but to accept the premise. He sees this as an outcome rife with opportunity to bring virtue back to the sciences. He says, “there are grounds to think, these effects would not only have a gradual influence in repairing the too much defaced sense of virtue in the world” (6). Berkeley believes that his argument will lead to a course correction in the sciences, restoring God and “those sacred mysteries, which are above the comprehension of our faculties” to their rightful place at the center of culture (6).