10 Life-Changing Quotes From Neil Degrasse Tyson's Commencement Speech

On Friday, at the University of Massachusetts Amherst, world renowned astrophysicist Neil deGrasse Tyson delivered one of the most poignant, entertaining and enlightening commencement speeches you'll ever hear.

In typical fashion, he was simultaneously humorous and philosophical, effortlessly combining general advice with reflections on politics and science. In the process, he revealed many of life's greatest truths.

Tyson's greatest gift is his ability to make the complexities of the universe both comprehensible and palatable to the masses. His talents were definitely on display during his eloquent speech.

He summarized the theme of his speech as, "things that you should know going forward in life." For young people graduating from college, there is not a more apt topic.

Here are 10 quotes from Neil deGrasse Tyson's commencement speech that perfectly explain life:

“Your grades, whatever is your GPA, rapidly becomes irrelevant in your life.”

There are a lot of intelligent, kind, inspiring and successful people out there who were terrible students.

Grades are not a comprehensive reflection of character, and life is not defined by who you were in college. We survive and thrive by evolving, not by focusing on the past.

If you didn't do well as a student, ask yourself why that is without making excuses. But also remember that every single day is another chance to change and another opportunity to turn it all around.

"The most dangerous people in a free society are those who don’t know... It's OK to not know. But if you don’t know, but think you do know… That is dangerous. Those are the signs of the end of an informed democracy."

Remember that learning is a lifelong endeavor. Nobody’s opinion is sacrosanct. We all have the capacity to err. It takes courage to admit when you’re wrong.

Progress ends when people begin to assume knowledge is finite. Ignorance is contagious.

Democracy is impossible without an informed citizenry. It cannot persist unless common people are willing to constantly ask questions, particularly of those in power. This is how a truly free society is established.

“Science matters."

Regardless of how boring you think it is, science is the reason you're alive and breathing.

The perpetuation of human civilization depends on innovations and technology -- the byproducts of scientific inquiry and research.

Indeed, our survival and advancement depends on science. If we choose to ignore it, we will suffer the consequences.

“It has become a pastime to blame politicians for the ills of the world... If you have an issue with politicians, it’s because you have an issue with your fellow citizens who put them there."

It's important to hold those in positions of power accountable, but we can't forget who put them there in the first place. We are all to blame for the condition of society.

None of us can afford to sit on the sidelines in life.

Politics matter just as much as science; they dictate so many aspects of our lives. If we choose to assume that our vote doesn't count and our voice doesn't matter, we've placed our future into the hands of others.

Participate. Don't complain without engaging, it's counterproductive.

“The laws of physics affect us all. Objective truths are true, whether or not you believe in them."

You can't fight gravity, it will always win.

There are certain observable truths in this world we cannot afford to deny.

When evidence mounts against what we believe, we have to be willing to acknowledge we were wrong.

Accepting the truth can be difficult sometimes, but the first step toward solving a problem is recognizing there is one.

"I think on some level, role models are overrated... If you require a role model who looks just like you to be something you wanna be and you can't find one, is that a reason to not be what you wanna be? No!"

Don't define your life based on other people's accomplishments.

Beyond simply breathing, life's greatest gift is that we all get to choose our own paths.

Remember that your identity is entirely up to you. You don't need anyone else's approval. You were free from the moment you were born.

“The universe is bigger than you are.”

You are not the center of the universe, but that doesn't mean you don't have value. As Tyson once said during an interview with Time:

When I look up at the night sky, and I know that, yes, we are part of this Universe, we are in this Universe, but perhaps more important than both of those facts is that the Universe is in us. When I reflect on that fact, I look up — many people feel small, ’cause they’re small and the Universe is big, but I feel big, because my atoms came from those stars.

We are all interconnected and equally important.

"Do not forget that Earth is really good at killing you... Ninety-seven percent of all the species on Earth that ever existed are now extinct... It's our ingenuity, in spite of that fact, that prevents it."

There's so much we don't know about both our planet and the universe it resides in.

Humans cannot afford to assume they have more power than nature -- it's ruthless. Respect the world around you, and cherish the environment.

Innovation is vital to our existence and it's impossible without promoting and valuing education, science and nature.

"I don’t know what has happened to the world, but you’re up next in the batters box.”

The world is constantly changing. Every generation has different experiences. In some ways, society has changed for the better; in others, it's regressed.

It's up to new generations to step forward and assume roles of leadership and to question why things have gotten to where they are.

Challenge the status quo. Don't assume those in power have your best interests at heart. Push for transparency, dialogue and accountability. And when the time comes, tell the next generation what must be done.

“We live in a world where not everyone has the urge to help others… It is OK to encourage others to pull themselves up by the bootstraps, but if you do, just remember that some people have no boots.”

Our society values individualism and hard work, but neither of these are guarantors of success, or even survival.

Not to mention, no matter how successful we may be, none of us got to where we are completely alone. Everyone receives help somewhere along the way.

Many of us have benefited from advantages we aren't always cognizant of -- remember that it could always be worse, and there are others out there less fortunate than you.

A human being's worth is not equivalent to his or her wealth; we all have value.

Treat others with dignity. No person deserves immediate disrespect and disdain, particularly not society's most vulnerable members.

Watch the full speech below: