question I wonder what your support for this interpretation of humans experiencing Nature as progress might be. There’s abundant evidence in media of various sorts — good, bad, or indifferent in quality — of people who contrarily do not experience the overall course of Nature as progressive at all, but instead as destructive and teleologically negative, especially today in conditions of global warming, cyclones, tornados, earthquakes, oceans rising, meteorites, and so on.
answer If you look closely, all those unpleasantnesses you mention do not pertain to overall existence at all but are the result of mistaken views, immorality and mismanagement. When we say how man experiences the course of Nature we of course mean man unencumbered by these contingent shortcomings and mistakes that impair his vision, understanding and accomplishments – the reference standard is overall existence and not failing mankind.
question I would agree with you that the objective of the Middle Way is to reconcile us with existence. Or to be more precise, it helps to understand life as it is. This is a condition for being to go forwards. However we are influenced by many things like greed, hatred and ignorance. These can take us backwards. The way to go forwards then is to develop the Eightfold Path. Or rather the Eightfold Path develops when there are conditions for its development. These conditions are the intellectual understanding of the Eightfold Path.
answer You are asked to accept the preeminence of existence over mankind, and that existence cannot, by definition, be anything but just right as it is, and that the Eightfold Path is an ongoing reflexion at the level of our personal lives of existence as a whole becoming over time. We must not see the Buddha’s Middle Way devoid of extremes as an attitude or method that will enable us e.g. ‘to escape from the realities of life’ or ‘to make it somehow in spite of things’, but we must understand the Buddha’s most fundamental teaching correctly as the means to reconnect and reconcile us with wondrous overall existence as a whole as it truly is. We must, in fact, accept that to live the way existence as a whole is, and not some idealized form of humanity, is what is to be sought after by men.
question I am not familiar with the term Advayavada.
answer We gave the name Advayavada Buddhism to the radical non-dual standpoint of the Madhyamaka school of Mahayana Buddhism to which we specifically adhere. A sound explanation of the term ‘advayavada’ can be found in for instance professor T.R.V. Murti’s The Central Philosophy of Buddhism: “The sole concern of the Madhyamaka advaya-vada is the purification of the faculty of knowing. The primordial error consists in the intellect being infected by the inveterate tendency to view Reality as identity or difference, permanent or momentary, one or many etc. These views falsify reality, and the dialectic [of the Madhyamaka] administers a cathartic corrective. With the purification of the intellect, Intuition emerges; the Real is known as it is, as Tathata [advayata; non-dual suchness] or bhutakoti [reality-limit; the extreme limit beyond which there is nothing which can be known]. The emphasis is on the correct attitude of our knowing..” It is in this sense that we use the term ‘advayavada’.
question What you say seems to me to be an essential teaching of the Mahayana in its complete form. The Unborn Infinite Reality can never be less than Perfect and Whole, and is the True Essence of all Beings, and is ever present. All that is needed is that, in perfect simplicity, we turn to That, and realize that the human manifestation of life is just an imperfect reflexion of That. Simple! but not easy. That is the problem. If we realize what we are, how do we remember to continue to realize it moment by moment, rather than seeking to hold on to the vision of the past?
answer Everything is, indeed, as right as it can be, and the Middle Way devoid of extremes is a perfect reflexion of it at the human level. As for your question, our answer would be that you must see that ‘vision of the past’ for what it really is: a highly selective subjective recollection in the present of things no longer there – please understand that life only happens Now.