"What do you believe in?"
At Simon's question, Ren hesitated.
"Believe? In what?"
"Anything. What are you certain of?"
Ren thought. "Mathematical theorems, maybe?"
"That's knowledge. Different from belief."
"Different?"
"Knowledge is justified true belief. But belief can exist without justification."
Ren asked, "So what is belief?"
"Subjective conviction. Believing even without evidence."
"Without basis?"
"Sometimes with basis. But it transcends basis."
Ren pondered. "Why transcend basis?"
"Because basis alone can't drive action."
"Action?"
Simon explained. "Do you believe 'the sun will rise tomorrow'?"
"Of course."
"That conviction has no logical basis."
"Hume's problem?"
"Yes. The problem of induction. Past patterns don't guarantee future ones."
Ren countered. "But physical laws—"
"Physical laws were also obtained inductively."
"So nothing is certain?"
"Logically, no. But practically, we believe."
Ren nodded. "Belief is practical necessity?"
"One aspect. Pragmatism's view."
"Others?"
"Identity. Beliefs define the self."
Ren asked, "Self-definition?"
"What you believe shows who you are."
"Belief is personality?"
"A large part. Religion, politics, values."
Ren thought. "But beliefs change."
"They change. But changing is difficult."
"Why?"
"Beliefs are tied to emotions. Not just reason."
Ren nodded. "Confirmation bias."
"Yes. Collecting only information supporting beliefs."
"Losing objectivity."
"Human destiny. Complete objectivity is impossible."
Ren looked at the window. "So what to do?"
"Skepticism. Keep doubting your beliefs."
"Descartes' methodological doubt."
"Yes. But can't doubt completely either."
"Why?"
"Doubting also presumes beliefs."
Ren laughed. "Recursive problem."
"Philosophy's constant."
Simon showed another angle. "Beliefs have degrees."
"Degrees?"
"Weak and strong beliefs. Different levels of conviction."
"How is conviction determined?"
"Amount of evidence, emotional investment, social support."
Ren thought. "When many believe, belief strengthens?"
"Social proof. But majority isn't always right."
"Galileo's example."
"Yes. Science history is full of minority being correct."
Ren asked, "So what should we believe?"
"No easy answer. But there are guidelines."
"For example?"
"Falsifiability. Hold beliefs that can admit error."
"Popper's philosophy of science."
"Yes. Being revisable."
Ren nodded. "Flexible beliefs."
"Rigid beliefs become dogma."
"But too flexible?"
"Beliefs thin out. Balance is needed."
Ren stood up. "Is belief a bet?"
"Close to Pascal's wager. Choice amid uncertainty."
"Taking risk."
"Believing is risk. Possibility of betrayal."
Ren thought. "But there's also risk in not believing."
"If you believe nothing, you can do nothing."
"Foundation for action."
Simon smiled. "Beliefs are like maps."
"Maps?"
"Not perfect. But without them, you get lost."
Ren nodded. "Imperfect but necessary."
"Yes. What matters is continually updating the map."
"Learning."
"Learning beliefs. That's growth."
They left the library. Holding beliefs, but also doubts.
Ren murmured, "Believing takes courage."
"Courage and humility together," Simon answered.
What to believe. That determines life. But there's no single answer.