Let us add a little depth to the metaphor.
The human being – and the human race, by expansion – possesses two drives which we in the modern world call “Progressive” and “Reactionary.”
Left and Right, or “To subdue the earth” and “To heed the natural order.”
Now, the metaphor is that of Cthulhu, swimming. The current pulls everything to the right, toward the natural order, terminating in a sheer fall – certain death. Therefore, Cthulhu swims left, to escape the turbulence and danger of the natural order.
The further he swims left, the less imminent the danger. He might finally relax in the water, even become playful. Yet, dangers still exist, and since he knows everything to the right becomes more threatening, he swims left.
And now the water is much calmer, still pulling but requiring very little effort to resist. Cthulhu might begin to impose his own design on the river, building a place to be seated by the bank or small dams to break the water. He will lose the exercise of those muscles which preserved him in the rapids, in favor of skills that enhance his pleasure and comfort in these less troubled waters.
New dangers await. Stagnant water harbors bacteria. His muscles have atrophied – if he wanders too far down river, he will surely drown. Other creatures compete for food, and even as the apex predator he can be overwhelmed by a mass of them. Moreover, there is an indescribable sense of discomfort, of not quite fitting in one’s environment, which the great beast cannot understand. That, quite simply, is that he was made to rule in stronger waters, to challenge himself, to conquer mighty forces.
Proceeding left has always brought him pleasure and comfort – progress – and so he swims further left.
The metaphor can continue, but it will become complicated, even convoluted – if it has not already, for your tastes. Let us look and see something.
There is a sense of melancholy about this metaphor, I think. That is, Cthulhu – the complete body of a human society – is never finally satisfied and safe. And someday he will die, his body carried along, ever more rapidly over the edge.
The human restlessness is such that it will want to challenge the rapids at times, but not for long. Wanting for some activity to challenge his mind and body, imagining even that his survival still depends on it, man swims ever Left, requiring that he impose his will more and more completely on reality.
Somewhere up the river, he thinks, is Utopia. Then he will be happy.
Now, “up” is correct, but the river is two-dimensional. The way out of the river is not upstream, but up, out-of-stream.
If this seems like nonsense, or incredible, or the perfect answer – welcome to religion. Religion is the pull of humanity up out of the river of this world. It is the third dimension, which might elicit these varied responses from two-dimensional creatures. One’s subjective response does not render it void.
Indeed, a properly ordered religion must position itself up, out of the river, and from that height throw down a rope. If Cthulhu – a human society – will grab it, he will be saved both from the dangers of the Left and Right. And it must be a strong rope, held up by a mighty arm.