Why is the notion of “living in the now” or “moment” nonsensical? Well, for one thing, it cannot literally be done. There is an unavoidable time lag between what is and what is being perceived due to the requisite medium of the sensory organs, and so the best a Buddhist could hope to do is press his lax face against the Samadhi-proof and well-tinted windows of perception.
For another, to ignore the past is not only to live in the present without context, but is to deprive oneself of the capacity to make educated choices as to the next course of action. Though I suppose the Now-person would not waste time considering that anyway, so blind he would be to anyone coming up from behind with a knife. So too with respect to what he might be a mere step away from slamming his stupid hanging head into, so fixed is he on his own two filthy fucking feet and that upon which those aimless soles press their weight.
And yet at times these Now-people demand more. The moment is not enough. They want you to live in the Here and Now.
At first this may merely sound like a rewording, but closer inspection reveals it to be emphasizing not just time and space, which seems covered well enough by the Now, but also one’s conscious attention, expressed as the Here distinct from, but with its implied proper placement in, the Now.
This may seem silly: how could one have their attention in the Now and yet not be Here? Well, they’re indicating they want your face pressed up against the glass, and it doesn‘t have to be. Even with our attention directed at the Now, we can be in one of three vantage points in terms of consciousness.
We have the first person perspective, where we see the world as filtered through our senses and our own values, beliefs, and personal history. We also have a second person perspective, which allows us to both step outside ourselves and look at ourselves from an “anonymous” outside perspective and allows us, through empathy, to slip into another person’s perspective, experiencing how the world must be for them. The last in line is, of course, the third person perspective, which allows us to detach from everything, rise above and look down on it all as a whole.
These are all very important perspectives.
And exclusion from all but the first-person leaves one a castrated soul, so to Hades with your prejudice against other temporal and vantage points, you wretched Now-people.