Could you imagine with the absence of memory and reason?

Of course, within the context of this world, memory serves its purpose...making it to appointments, letting the cat in at night, restocking milk and bread, returning phone calls, etc. Yet memory pulls us all too often into the past, anchoring us into this world of duality. We remember the harm we perceive someone did to us, the lost love from 20 years ago, our unfulfilled goals, empty promises that were made to us, etc., and we dwell in regret or anger or hatred. Or, conversely, we remember former successes, kindnesses done to us, gifts we received from others, experiences that filled us with contentment or a sense of adventure, etc., and perhaps for these we still long, desiring to repeat them. This, too, keeps us unaware of being in the moment.

Reason is based on what is "known" in this changing world of polarities, which come and go, shift and move, rise and fall. Information is not static, nor is it universally applied within our illusionary world.

As to imagining, it can only reference the past or future, neither of which is real, for neither exists, except in the mind.

However, imagining has its use in that it may eventually lead us out of the dream and waken us from our sleep by offering possibilities of, whispers about, prods to a higher consciousness beyond our restrictive experience. For this use reason is unnecessary, and the only memory referenced is the remembrance of what we have forgotten...our unbroken connection to God/Source/All That Is.

i am Sirius

Yep. My imagination was a lot better when I was a child and didn't have memories or the ability to judge my own thoughts.

Without memory we wouldn't remember what we imagined.

Yes, everytime I hear my neighbor quoting what Rush Limbaugh said that day.

Sure. It would be like a wildly chaotic dream that you forget the moment you wake up.