Science & Tech, Business

Be a Skeptic: Ask Questions

Neil deGrasse Tyson

Lesson time 12:13 min

Asking questions is a tried-and-true component of scientific thinking. Neil talks about the processes behind informed skepticism as well as how to evaluate incoming scientific data.

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Topics include: Are You Intellectually Lazy? · Skepticism: The Path of Inquiry to What Is True · How True Is Objectively True?


[MUSIC PLAYING] - So imagine someone comes up to you with some crystals, and they tell you that there's sort of a crystal energy embedded within them, and if you rub them together, this energy field will release, and it will enter your body and cure you of your ailments. All right, i have several things to say about that. One, it is equally as intellectually lazy for you to say, great, give them to me, how much, here's my money, I'll use them tonight, as it is to say, this can't possibly be true, get out of here, you're a charlatan. Both of those are equally intellectually lazy. If you're just taking what the person says, giving them money, that person could be exploiting your ignorance of the natural world and how it works. If you are rejecting what the person says, you didn't give yourself a chance to probe whether or not what the person said could be true. So what you need to do at this point is start asking questions. Where are these crystals from? What are they made of? What frequency of energy is generated when you rub them? On what ailments has this been tested? Can you show me those test results? Tell me about them so I can look them up. Let's look them up together. Was that research result verified by others? Is there a kind of disease that it does cure better than another disease that it maybe doesn't? You start asking questions. If only one experiment found that result or two or even only three, it's susceptible, because you could have been biased. You could have done an experiment that didn't really test what you were looking for, but masqueraded as though it was. There is all manner of things that could go wrong. I was observing the universe from a mountaintop in the Andes for my PhD thesis, and there was a 5 and 1/2 or 6 magnitude earthquake in the mountain. This is the Ring of Fire, the Andes Mountains that connects with the Rockies and up through the Aleutian Islands and down through Japan. It's a continental plate that's shifting, and on the edges of that plate, you have tectonic activity, which includes, by the way, the San Andreas fault is part of this. So I'm there in the Andes Mountains, and I'm getting spectra of stars. This is where you get light from a star, break it up into its component colors, and analyze it, and in there is a trove of information, what color the star is, what the chemical composition is, how is it moving, how is it rotating. And this has to be precisely calibrated, which it was until the earthquake. Unknown to me at the time, the earthquake shifted the platform on which the spectrograph was located. I started taking data again, once we recognized that the structure was safe, the telescope dome. And I noticed it looked really different. I was still getting spectra, but it was wacky spectra. I could have said to myself, wow, the star changed in the last few minutes, and I've just made a discovery. Or, I said, wait a minute, we just had an earthquake. I wonder if something got knoc...

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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