How do we know what we know?

Most of what anyone knows comes from five places. We use our senses. We reason things out. We trust what other people tell us, which is called testimony. We learn from our own lives. And many people trust revelation or tradition: what they believe God or their elders have shown them. Everyone uses all five. Faiths differ in how much they lean on each one.

1 · MindWhat people believe, and how they know

This entry is the map for the whole site. Every answer here names which ways of knowing it leans on, so you can see the reasoning and not just the conclusion.

What each tradition or community says

We're Christians, so we list what Christians believe first. Every other section is checked by someone from that faith or community.

Christianity

Christians lean on revelation in scripture, the testimony of the apostles and the experience of God, and treat reason as a gift. Luther thanked God for giving him his reason and all his senses (Small Catechism, First Article).

Judaism

Torah received at Sinai and handed down through tradition, then studied with intense reasoning and debate. Study itself is a form of worship.

Islam

The Qur’an as revelation, the Prophet’s example passed down through carefully checked chains of narrators, and reason (‘aql). The Qur’an repeatedly urges people to reflect on the signs in creation (Qur’an 3:190-191, summarized).

No religion

Many secular people lean most on the senses and reason, especially science, while relying on testimony every day: doctors, teachers, the news.

2 · HeartWhat it feels like

Think about your birthday. You don’t remember being born. You know the date because someone you trust told you, and a document backs it up. That’s testimony, and it’s how most knowledge works.

Philosophers call the study of knowing epistemology. It sounds dry, but it answers a very human question: why am I so sure, and why is my neighbor just as sure of something else?

For neurodivergent minds that like to see the system, this is the system. Once you can name how you know something, conversations with people who disagree get a lot less scary.

Nobody has ever proven to me that my coffee isn’t decaf. I trust the person behind the counter. Most of life runs on that kind of trust, and so does most of faith.Neighbor Radio

3 · HandsHow to be a good neighbor

Jesus reached people through every way of knowing. He told stories that made people reason their way to an answer (Luke 10:36). He let doubting Thomas see and touch (John 20:27). And he called himself the truth, someone to know and not only a fact to learn (John 14:6).

This weekNext time you disagree with someone, ask: “How did you come to believe that?” Then listen to the whole answer.

SourcesWhere it is in the scriptures

New Testament

Luke 10:36 Read it in the World English Bible on Free Scripture
John 20:27 Read it in the World English Bible on Free Scripture
John 14:6 Read it in the World English Bible on Free Scripture

Qur’an

Qur'an 3:190-191

Bible passages are quoted from the World English Bible. Other sacred texts are summarized, with references so you can find them.

Plain wordsWhat do these words mean?

Testimony: A personal story of faith: what someone believes and why. In court, it means a witness’s account.
Revelation: Something people believe God has shown or told them. Also the last book of the Bible.
Catechism: A summary of a church’s teaching, often written as questions and answers.
Torah: The first five books of the Hebrew Bible, Genesis to Deuteronomy. Jews read from a Torah scroll in the synagogue. The word also means “teaching.”
Qur’an: The holy book of Islam. Muslims believe God revealed it to the Prophet Muhammad through the angel Gabriel.
Prophet: Someone believed to speak a message from God.
Secular: Not religious, or not tied to any religion. A secular government doesn’t take a side on faith.

All the words →

Four questions to take with you

From Jesus' story of the Good Samaritan, about the stranger who stopped to help. We call it the Samaritan Test.

Did they see? Or look right past?
Did they stop? Even when it was inconvenient?
Did it cost them? Time, money, comfort, reputation?
Did they treat the person like a person? Not like a label?

Try it on: one thing you’re sure is true about a group you don’t belong to. Where did you hear it?

Quick questions

What is epistemology?

The study of knowledge: what it is, how we get it, and how sure we can be.

Is faith the opposite of knowledge?

Not in most traditions. Faith usually means trusting a source, which is how a lot of ordinary knowledge works too.

Sources and research

How this answer was made

Written in plain words by the Neighbor Radio team. Each faith's and community's section is checked by someone from that faith or community. Until then, this page says so. Spot something wrong? Tell us. We read every note and fix mistakes.