Animals have different sensory capabilities compared to us humans. Cats, উদাহরণস্বরূপ, can hear up to 60kHz, while the highest note we have ever heard was about 20kHz. দৃশ্যত, we could hear that high a note only in our childhood. সুতরাং, if we are trying to pull a fast one on a cat with the best hifi multi-channel, Dolby-whatever recording of a mouse, we will fail pathetically. It won’t be fooled because it lives in a different sensory world, while sharing the same physical world as ours. There is a humongous difference between the sensory and physical worlds.
The sensory world of snake includes infrared vision. সুতরাং, to a snake, our 4K-3D projection of a rodent will look about as realistic as a black and white movie looks to us. We get totally impressed by the amazing olfactory feats of a hound, but we have no way of knowing what the corresponding sensory world looks or feels like. Take a bat as another example. It pinpoints the insects that flit about in the night using echolocation and preys on them. To a bat, our hifi, super-HD reproduction of the night will look insipidly flat and unrealistic.
I have a reason for listing all these distinctions between the sensory and physical worlds as experienced by various creatures. We implicitly assume that our sensory world is the real physical world out there. When we describe the sensory world of a bat, উদাহরণস্বরূপ, we say something like, “ঠিক আছে, here is what’s সত্যিই going on. The insect is flying from this point to that point, while the bat is moving from here to there. The bat emits a series of pings that reflect and reach the bats here and here, and the bat’s brain is hardwired to identify the reflections as the insect and determine its real speed, direction etc. It then plots an intercept path and catches it.” The whole description is that of an encounter in আমাদের sensory world, with the tacit assumption that it is the real physical world — as though we humans have some private access to the physical reality that the bat doesn’t.
এই, অবশ্যই, হয় সম্পূর্ণরূপে অচল. The bats don’t actually hear the pings they send out or their reflections. They just have a sense modality that puts them in a navigational sensory world, with its own space-time geometry, where they see or sense their prey and move along the right trajectory to catch it. It is not as though they have figured out the real space-time geometry, cleverly using their echolocation to navigate in it, while we can just see the physical reality for what it is. They have a projection of the physical world, which results in a sensory world that they can effectively function in. We have another projection, which gives us another sensory world that we can thrive in. What the bats have is certainly না a projection of our sensory world through the apparatus of their echolocation.
এখন, if I have convinced you that our sensory world is distinct from the physical world out there, I have hit my mark. The rest is easy — it is the অবাস্তব ইউনিভার্স.