Whatever it was, Avenarius and Mach are right in the respect that without consciousness there is no matter and vice versa, though here they exhibit significant fluctuations, then reducing matter to sensations, then claiming that matter as some substance still exists.
In particular, Mach reduces matter to sensations, indicating on this in the following fragment: “Sensations are not “symbols of things”. The “thing” is rather a mental symbol for a complex of sensations of relative stability. Not things (bodies) but colours, sounds, pressures, spaces, times (what we usually call sensations) are the real elements of the world” [15, p. 473].
At the same time Avenarius believes that each person is a sensing substance, i.e. he recognizes existence along with sensations (consciousness) of some matter though accurately doesn't share them: "So as … neither the experience nor the right conclusions from it do not give the right to consider sensations as a result of motion, it is appropriate to recognize sensations as a property of the respective substance and therefore to allow the existence of sentient substances. At this is especially valuable for us the fact that we know ourselves as the sensing substance and in our inner experience sensation is given with more certainty than is substantiality" [3, §91].
But not everything is exactly as believe Mach and Avenarius because on the basis presented by them it is impossible to draw conclusion on absence in general for the person of the objective reality, more precisely, to draw a conclusion on lack of things, which are independent of consciousness, for the following reasons.
In infinite and eternal Uniform consciousness (the active) and things (the passive) are merged together, and in a different way out of time can't be, and it isn't necessary to speak here about dependence or independence of things from consciousness.
But timeless Uniform as the infinite which remains invariable, is manifested through own holographic projection which exists in time, and three-dimensional measurement as a derivative from it the person can observe. And this changeable reality round the person is quite independent of him so how he isn't capable to change motion of stars and even weather on Earth.
Therefore, Avenarius and Mach are wrong in their denial of the existence of objective reality for the human, or more precisely, – denial of independently existing from human things, essentially bearing in mind only something with which one is confronted in its activity, pointing to the inseparability of subject and object in the experiment.