How can the existence of ʿālam al-ġayb—the Unseen World, including angels, Paradise, Hell, and so on—be inferred through scientific reasoning?

As materialism came to dominate academic thought, belief in the metaphysical realm has increasingly been viewed as primitive and naïve. Yet, belief in al-ġayb is a fundamental part of a Muslim’s faith. The original meaning of al-ġayb in Arabic is “that which is hidden from our physical senses,” and it is in this sense that the term appears in the Qurʾān. It denotes the opposite of ḥāḍir, which refers to what is present to our senses and perceptible. In other words, the world we can observe and interact with is referred to in the Qurʾān as the “seen world,” while the realm beyond human perception is called the “unseen world.” The difficulty arises from the assumption that all knowledge must be scientific in nature. While there is no denying that science excels in describing the physical world, the unseen encompasses dimensions of reality that can only be known through Divine Revelation. Belief in any supernatural being—such as the angel Gabriel—or in any metaphysical reality involves accepting truths that lie beyond the limits of space, time, and human perception, and thus beyond the reach of empirical science. The unseen world includes all that is hidden from our physical senses, such as Allāh and His attributes, invisible beings (angels, Satan, jinn), events preceding human existence,¹ the lives and missions of past Prophets, and all future events including resurrection after death, the Day of Judgment, Hell, Paradise, and so on. Materialist atheists, however, refuse to accept anything they cannot perceive with their senses. They generally use the term “dogma” to describe any belief that, in their view, is held by believers “unquestioningly” and with “undefended certainty.” Common criticisms include statements like, “You Muslims accept whatever the Qurʾān says without investigation,” or “It is not logical to believe in something without seeing it and straining it through the filter of the mind,” or “Belief is confirmation after seeing.’’ In truth, such objections are simply denials of Islam itself, for which of the six pillars of faith is visible to the eye?² Belief in the unseen is what defines a believer. Without it, one cannot claim to have any faith in Islam at all. To become a Muslim, one must testify, “I bear witness that there is no god but Allāh, and Muḥammad is His Messenger”—a declaration that rests entirely on faith, without having seen either Allāh or the Prophet Muḥammad (PBUH). Faith, then, is essential to the character of a Muslim. The Prophet (PBUH) defined faith with these words: “Faith is to believe in Allāh, His angels, the meeting with Him, His Messengers, and to believe in the Resurrection.”³ These are known as the “six articles of faith.” Each one calls us to believe in something we have neither seen nor experienced firsthand—this is the very essence of faith. Therefore, contrary to what atheists claim, belief is confirmation without seeing. Consider this: if I take an orange out of my pocket and say, “This is an orange,” a person’s confirmation after seeing it is not faith—it is simply acknowledging what they see. But if I say, “There is a diamond object in my pocket,” and someone chooses to believe me without seeing it, that is faith. Once the diamond object is seen, any confirmation of it is no longer faith, but merely a statement of what is visibly known. The very purpose of faith, then, is to believe in that which cannot be seen or empirically verified. Allāh refers to those who demand something visible or tangible in order to believe, saying: {They say, “Why has no ˹visible˺ angel come with him?” Had We sent down an angel, the matter would have certainly been settled ˹at once˺, and they would have never been given more time ˹to repent˺} (Qurʾān 6:8). Metaphysical matters lie beyond the scope of human knowledge. In other words, one cannot acquire knowledge of such matters through the use of the mind or senses. Yet, as Muslims, we are required to believe in whatever Allāh and His Prophet (PBUH) have communicated to us, even if it lies beyond human comprehension or cannot be proven by empirical means. Paradise, Hell, the Bridge of aṣ-Ṣirāṭ,⁴ and all events related to the Hereafter cannot be substantiated by reason or intellect alone—but true Muslims attain the highest level of faith by saying, “If Prophet Muḥammad (PBUH) said it, then it is certainly true.” Faith is not something that is attained through investigation or analytical reasoning; rather, faith is to believe without seeing. The necessity of believing in the unseen is emphasized right at the beginning of the Qurʾān, where Allāh praises the pious, saying: {this is the Book! There is no doubt about it—a guide for those mindful ˹of Allāh˺ who believe in the unseen establish prayer, and donate from what We have provided for them…} (Qurʾān 2:2–3). That is, belief in the unseen is a defining trait of the pious, and Allāh mentioned it even before acts of worship such as prayer and charity. A lack of faith in the unseen is, in essence, no faith at all, as Allāh says: {are they awaiting the coming of the angels, or your Lord ˹Himself˺, or some of your Lord’s ˹major˺ signs? On the Day your Lord’s signs arrive, belief will not benefit those who did not believe earlier...} (Qurʾān 6:158). Allāh informs us that He and His angels belong to the unseen and will become manifest on the Day of Judgement. Belief in Allāh and His angels is required during our time on earth, and if a person does not believe in them without having seen them, their faith will not be accepted. Those who say, “Everything conveyed by the Messenger of Allāh (PBUH) is true,” are the ones who will attain salvation. In short, our response to those who demand a rationale for believing in something beyond sensory perception is that we are not in a position to deny the existence of what lies beyond our senses. The mere fact that something cannot be seen or detected does not entitle us to reject its existence—especially when it is well known that even in this world, there are countless realities beyond the reach of our senses. Take the human soul, for instance: no one knows its true essence, yet no one can deny that it exists and sustains life. Furthermore, certainty derived from a trustworthy source can provide just as much conviction as direct observation. That is, when something is confirmed by an honest and reliable authority, it carries the same weight as if we had witnessed it ourselves. Thus, we Muslims believe in angel Gabriel and the unseen world beyond our perception, because the truthfulness of Prophet Muḥammad (PBUH) in conveying the Divine Message has been firmly established. Real faith does not require testing what the Messenger of Allāh (PBUH) conveyed against intellect or experience, for “the Prophet whose truthfulness in what he communicated from Allāh has been proven by evidence and miracles was truthful in everything he conveyed about Allāh.”⁵ If we affirm what the Prophet (PBUH) conveyed merely because it aligns with reason, then in truth we have affirmed the intellect, not the Messenger—or we have affirmed both the intellect and the Messenger together, in which case our trust in the Messenger is incomplete. And where confidence is incomplete, faith itself is absent. In short, the unseen world is not myth or legend—it is real. However, the human mind cannot access the metaphysical realm, nor can human imagination encompass realities that lie beyond the reach of our senses.