Max Planck was a German physicist whose work on energy laid the foundations of quantum theory. In 1900, he proposed that energy is given off in tiny packets, or “quanta”, an idea that changed physics forever. He was awarded the Nobel Prize in Physics for 1918.

Planck was also a thoughtful writer on science, mystery and the mind. Here are five of his well-known lines to reflect on.

1. On consciousness

“I regard consciousness as fundamental. I regard matter as derivative from consciousness. We cannot get behind consciousness.”

Planck said this in a 1931 newspaper interview. It’s a philosophical view, not a scientific finding, but it invites us to wonder about the nature of awareness.

2. On mystery

“Science cannot solve the ultimate mystery of nature. And that is because, in the last analysis, we ourselves are part of nature and therefore part of the mystery that we are trying to solve.”

This line, from his book Where Is Science Going?, is a beautiful reminder of humility. We study the world from the inside.

3. On faith

“Over the entrance to the gates of the temple of science are written the words: Ye must have faith.”

Planck believed that scientists rely on a kind of trust: that the world is orderly and that it can be understood.

4. On new ideas

“A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”

This wry observation, from his Scientific Autobiography, reminds us how hard it can be to change our minds, even for brilliant people.

5. On mind and matter

“We must assume behind this force the existence of a conscious and intelligent Mind. This Mind is the matrix of all matter.”

Planck spoke these words in a 1944 lecture. They reflect his personal beliefs, and many scientists see things differently, but they show how deeply he thought about the mystery behind physics.

Reflecting on Planck’s words

You don’t need to agree with Planck to find his words thought-provoking. They invite us to hold our knowledge with humility and to stay open to wonder.

How little is enough

Choose one of these quotes and write it somewhere you’ll see it this week. Notice what it brings up for you.

For more, read the energy-verse idea: what physics does and doesn’t say.

For a quiet place to write your way through this season, you’ll find a guided journal on the Guides page.