Physical bodies are finite, corruptible, but are human beings just their bodies (and their finite minds)? There is a mysterious, undefinable, and unmeasurable entity called consciousness which appears to pervade all sentient beings and nature in general. Nature, all life, is conscious – dare we say? This entity – consciousness – is undeniable, for it is our most direct and unfalsifiable experience. Consciousness – by consensus of a majority of physicists – escapes all parameters of physics, neurophysiology, and brain studies. But not only consciousness, but so-called matter is also in the same category of the intrinsically unknowable, even if there are methods for measuring and experimenting with such entity as matter-energy.
Again, no one knows what eternity might be, such are the limitations of our means of understanding reality, even though physics and mathematics come to our aid in this and also with the phenomenon of space (space-time). What is more, philosophy and metaphysics have a better grasp of the extra-physical dimensions of reality aided and abetted as they are by (universal) intuition. For metaphysics time does not exist outside of our minds, and, rather than eternity-(duration), timelessness – or what is the same, that only the PRESENT exists – is what, as a concept, gives a semblance of reality to reality (all that is and ever has been) – incomprehensible to the unaided mind.