Science & Tech, Business

The Scientific Method

Neil deGrasse Tyson

Lesson time 14:13 min

When we use the scientific method in the quest for objective truths, nature is the judge and jury. Neil shares some remarkable astrophysical examples of how this method plays out in real life and in our vast universe.

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Topics include: The Search for Truth


[MUSIC PLAYING] - The scientific method is do whatever it takes-- whatever it takes-- to not fool yourself into thinking something is true that is not, or into thinking that something is not true that is. That's the scientific method, whatever it takes. And that pathway-- it's not straight. It's curved. It has off-ramps that lead nowhere. And you don't even know, of the paths that lay in front of you, which one is gonna get you to the right place. There's a lot of experimenting going on. In fact, that's the whole point of an experiment. And when you're doing research, the answer is not listed in the back of the book. There's not the teacher's guide that gives you the answers to what you're-- no. No, that doesn't exist. It's you and nature. And you know the cool thing about it? Nature is the ultimate judge, jury, and executioner. You can argue all you want, but if nature doesn't agree with you, you're wrong. Whatever bias you're bringing to the table, nature will decide. So you have to make sure that your methods and tools allow nature to manifest in whatever way it can to give you the guidance to where the truth lays. [MUSIC PLAYING] In one of my favorite examples in the history of science, William Herschel, the famous astronomer-- he's credited with the discovery of the planet Uranus. At this point, Newton's laws of motion and gravity are well in place. They tell us how planets are orbiting the sun, how moons are orbiting planets, and they are kept in their orbit by the mutual force of gravity between them. And we follow carefully the movement of Uranus in its orbit, and it's not obeying Newton's laws. So we're confronted with a challenge. Either we found the limits of the applicability of Newton's laws-- Newton's laws only work on so far away from the sun. Maybe you go too far away, they break down. That's a possibility. No one had ever tested Newton's laws that far out, so that's one possibility. Another possibility is, dude, Newton's laws have been explaining everything about planetary motion for the past century. Come on, now. We're not gonna give up on it that easily. Well, if you're not gonna give up on it, how do you explain it? Here-- maybe there's something else out there, another planet whose gravity is tugging on Uranus in a way that we haven't included in our equations. So the calculation was done. It's a hard calculation. It's one thing to have a planet and say, what's the gravity over here? It's another thing to say, how much gravity do I need over here in order to move this planet in a particular way? It's an inversion problem in mathematics that was very challenging, especially in the day when they didn't have computers. So we did the calculation. And we said, if Newton's laws are being obeyed all over, then there must be a planet there in the sky tugging on Uranus to make us think it's not obeying Newton's laws. So let's look for it. The word got out to the observatories. The two relevant names he...

About the Instructor

With a hit talk show and bestselling books, Neil deGrasse Tyson is one of the most popular figures in modern science. Now the influential astrophysicist teaches you how his mind works and how he connects with audiences. Learn to think like a skeptic, open your own mind through scientific literacy, distill data, and navigate bias to discover objective truths—and deliver your ideas in ways that engage, excite, and inspire.

Featured Masterclass Instructor

Neil deGrasse Tyson

Renowned astrophysicist Neil deGrasse Tyson teaches you how to find objective truths and shares his tools for communicating what you discover.

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