Questions No One Knows the Answers to (Full Version) | Summary and Q&A

March 17, 2012
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Questions No One Knows the Answers to (Full Version)


The universe is vast and there are unanswered questions about the number of universes and the existence of extraterrestrial life.

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Key Insights

  • 🤩 The universe is vast and contains billions of galaxies and stars, with the possibility of countless more in a multiverse.
  • ❓ Recent theories in physics, like string theory, suggest the existence of a multiverse with up to 10^500 universes.
  • 🛟 The question of extraterrestrial life remains unanswered, despite the likelihood of numerous life-harboring planets in our galaxy.
  • 🛟 There are various possible explanations for the lack of evidence of alien life, including the possibility of a superintelligent civilization imposing strict radio silence or the rarity of intelligent life.


On a typical day at school, endless hours are spent learning the answers to questions, but right now, we'll do the opposite. We're going to focus on questions where you can't learn the answers because they're unknown. I used to puzzle about a lot of things as a boy, for example: What would it feel like to be a dog? Do fish feel pain? How about inse... Read More

Questions & Answers

Q: How many universes are there?

There is no agreement on the number of universes, but leading theories suggest a multiverse consisting of up to 10^500 universes, each with different properties and laws.

Q: Why can't we see evidence of alien life?

There are several possible answers, including the possibility that a single superintelligent civilization has imposed strict radio silence, or that the evolution of intelligent life is rarer than assumed. It's also possible that we are not looking in the right way or at the right scale.

Q: Are robots or AI capable of becoming conscious?

The question of robot consciousness is uncertain. While some theories suggest that consciousness can emerge in complex systems, it remains unclear if AI can achieve true consciousness like humans do.

Q: Will we ever have conclusive answers to these questions?

The quest for knowledge and understanding is ongoing, and while we may never have definitive answers to some of these questions, the pursuit of knowledge and the unanswered questions themselves are what propel us forward.


In this video, the speaker explores unanswered questions that have puzzled him since childhood. He discusses questions about the universe, such as the number of universes and the existence of alien life, and explains that there is currently no consensus on these topics. Despite the lack of answers, the speaker finds excitement and wonder in diving into these questions, as they push the boundaries of knowledge and discovery.

Questions & Answers

Q: How many universes are there?

The speaker explains that there is no concrete answer to this question. While current theories suggest the existence of a vast multiverse with countless universes, the exact number is unknown. String theory predicts a multiverse with 10 to the 500 universes, an incredibly large number. Additionally, some physicists propose the concept of an infinite space-time continuum containing an infinite number of pocket universes. The speaker emphasizes that this ongoing exploration of the number of universes is an exciting time in the study of physics.

Q: Why can't we see evidence of alien life?

The speaker delves into the famous question asked by Enrico Fermi, "Where is everybody?" Despite the discovery of numerous exoplanets in our galaxy that could potentially support life, there is a lack of evidence for intelligent alien civilizations. The speaker presents various possible explanations for this, including the ideas that intelligent life may be rarer than assumed, that advanced civilizations could be hiding or extinct, or that they are using communication technologies beyond our current understanding. Additionally, the speaker suggests that our search methods might be inadequate or that life could exist on a microscopic scale, unnoticed by us.

Q: Do fish feel pain? How about insects?

The speaker recalls his childhood questions about whether fish and insects feel pain. He explains that these questions still puzzle him because determining consciousness and pain perception in non-human beings is challenging. While there is evidence suggesting that some animals, such as mammals and birds, have the capacity to experience pain, the subjective experiences of fish and insects are still debated. The speaker highlights the importance of ongoing research in understanding the inner lives of different species.

Q: Is there a God? And if so, how are we so sure that it's a He and not a She?

The speaker raises questions about the existence of a higher power and the assumptions made regarding the gender of God. He acknowledges that the nature of God is a deeply philosophical and theological topic, encompassing a wide range of beliefs. Different cultures and religions attribute different genders or even non-gendered qualities to their deities. The speaker emphasizes that the answer to these questions remains unknown and subjective, tied to individual beliefs and interpretations.

Q: Why do so many innocent people and animals suffer terrible things?

The speaker tackles the difficult question of suffering and its existence in the world. He acknowledges that this is a deeply philosophical and moral issue, one that has troubled thinkers throughout history. The problem of suffering is a key challenge for various religious and philosophical systems, and no definitive answer exists. The speaker suggests that exploring this question allows us to confront the complexity of the human experience and, in turn, appreciate the moments of joy and compassion that arise even amidst suffering.

Q: Is the future yet to be written, or is it already written and we just can't see it? But then, do I have free will?

The speaker contemplates the concepts of fate, free will, and the nature of the future. He ponders whether the future is predetermined or if individuals possess the ability to shape their own paths. The speaker admits that these questions remain elusive and perplexing, as they touch on fundamental philosophical and metaphysical notions. While no definitive answers are available, contemplating these questions can inspire a sense of wonder and push us to explore the nature of human agency and the mysteries of time.

Q: What is consciousness? Will robots become conscious one day?

The speaker explores the enigma of consciousness and its relationship to machines. He questions what consciousness truly is and how it emerges in living beings. While consciousness remains a topic of ongoing scientific investigation, no definite answers have been reached. The speaker also contemplates the potential for machines, such as robots, to develop consciousness. He acknowledges the possibility but emphasizes that it is still a matter of speculation. Exploring the nature of consciousness allows for a deeper understanding of our own existence and the potential capabilities of artificial intelligence.

Q: Am I just a biological machine? But then, why am I conscious?

The speaker delves into the philosophical question of human existence and consciousness. He ponders the nature of being human and questions whether we can be reduced to biological machines. While human beings can be described in terms of biological processes, the experience of consciousness remains a profound mystery. The speaker acknowledges that the origins and purpose of consciousness are still subjects of intense scientific and philosophical scrutiny. Exploring this question offers insights into our unique experience of being alive and self-aware.

Q: Are there other types of particles, laws, and properties in different universes?

The speaker discusses the intriguing possibility that other universes could be built on different particles, laws, and properties, as suggested by string theory and other physics theories. He explains that current understanding of physics allows for the existence of countless other universes with varying characteristics. These universes may operate under different physical laws and contain different types of particles, extending far beyond our imagination. While the specific details are yet to be discovered, the existence of diverse universes adds to the captivating complexity and mystery of the cosmos.

Q: Is our universe the only one, or are there other universes out there?

The speaker explains that the question of whether our universe is the only one or if there are multiple universes remains unanswered. While some scientists argue for a single universe, others propose the existence of a multitude of universes, forming a larger multiverse. The speaker mentions the concept of an expanding space-time continuum and the possibility of countless parallel universes generated continuously. The nature of our universe—whether it is an illusion or a part of a larger multiverse—continues to perplex scientists and philosophers alike.

Q: Does life exist only on Earth, or are there other life-harboring planets?

The speaker discusses the question of life beyond Earth and the potential existence of habitable planets in the universe. Relying on the discoveries made by the Kepler space observatory, he explains that there could be a vast number of planets in our galaxy alone that may support life. However, the lack of evidence for advanced extraterrestrial civilizations poses a riddle known as the Fermi Paradox. The speaker proposes various answers, ranging from the rarity of intelligent life to our limited search capabilities or the possibility that life exists on a scale or in forms we have not yet considered. Ongoing research and advancements in spectroscopy and the search for extraterrestrial intelligence aim to unravel the mysteries of life beyond Earth.


This video highlights the thrill of exploring unanswered questions that lie at the edge of human knowledge. It emphasizes that many profound questions, such as the number of universes and the existence of alien life, still lack definitive answers. However, the pursuit of understanding and the curiosity to explore these questions push humanity forward, driving scientific research and groundbreaking discoveries. The speaker encourages the audience to stay curious, as the quest for knowledge never gets dull, and the unanswered questions continue to inspire awe and wonder.

Summary & Key Takeaways

  • There are countless unanswered questions about the unknowns of the universe, from the number of universes to the existence of God.

  • The universe is unimaginably vast, with billions of galaxies and stars, and recent theories suggest the existence of a vast multiverse with different laws and properties.

  • The question of extraterrestrial life is puzzling, as there should be countless planets in the galaxy that could support life, but we have yet to find any convincing evidence.

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