Max Planck was told that there was nothing new to be discovered in physics. He was about to embark on a career in physics that would set that idea on its ear.

As a young student Planck had shown great promise in music, but a remarkable mathematics teacher turned his interest toward science. After gaining degrees from the Universities of Berlin and Munich, he focused on thermodynamics (the study of heat and energy). He was especially interested in the nature of radiation from hot materials. In 1901 he devised a theory that perfectly described the experimental evidence, but part of it was a radical new idea: energy did not flow in a steady continuum, but was delivered in discrete packets Planck later called quanta. That explained why, for example, a hot iron poker glows distinctly red and white. Planck, a conservative man, was not trying to revolutionize physics at all, just to explain the particular phenomenon he was studying. He had tried to reconcile the facts with classical physics, but that hadn't worked. In fact, when people refer to "classical physics" today, they mean "before Planck." He didn't fully appreciate the revolution he had started, but in the years that followed, scientists such as Albert Einstein, Niels Bohr, and Werner Heisenberg shaped modern physics by applying his elegantly simple, catalytic new idea.

Planck was an extremely successful physicist, receiving the Nobel Prize in 1919, but his personal life was marked by tragedy. He and his first wife Marie Merck had two sons and twin daughters; Marie died after 23 years of marriage. He remarried and had one more son. Planck's eldest son was killed during World War I, and both daughters died in childbirth. In 1944 his second son was executed for involvement in a plot to assassinate Hitler. Planck himself openly opposed Nazi persecutions and intervened on behalf of Jewish scientists. He praised Einstein in contradiction to the Nazis, who denounced Einstein and his work. He even met with Hitler to try to stop actions against Jewish scientists, but the chancellor went on a tirade about Jews in general and disregarded him. Planck, who had been president of the Kaiser Wilhelm Institute since 1930, resigned his post in 1937 in protest. After the war, the research center was renamed the Max Planck Institute and he was appointed its head.

"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."

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