Bertalanffy held that humans create their own reality, not because objective reality doesn't exist but because human knowledge depends on what humans are able and willing to perceive. "There are no facts flying around in nature as if they are butterflies that you put into a nice orderly collection. Our cognition is not a mirroring of ultimate reality but rather is an active process, in which we create models of the world. These models direct what we actually see, what we consider as fact."

The validity of knowledge is based on the perspective from which the same knowledge is perceived; it is like a Napolitan ice (cream cake) where the lemon truth is different from a strawberry truth; where what's is true in the chocolate layer at the bottom remains unaffected by what's is true in the vanilla layer at the top, neither affects the chocolate truth to the vanilla one. This Aldous Huxley's metaphor was a Bertalanffy's reference to his systems epistemology.

"The same table is to the physicist an aggregate of electrons, protons and neutrons; to the chemist, a composition of organic compounds; to the biologist, a complex of wood cells; to the art historian, a baroque object; to the economist, a utility of certain monetary value, etc." It can be claimed that obviously "all those views are valid and none is more authentic than the other." Though it could be also argued that "there is equal justification for the world views of science, the arts and metaphysics" this statement appears to be less obvious due to the generation of many diverse degrees of nihilist beliefs, which usually are easily spread among different groups of people who negate de facto the possibility of their brains to learn how to create reliable models of the objective reality around them.

"No world view, general systems theory included, is ultimate truth or ultimate reality. Each is a perspective or an aspect, with all-too-human limitations owing to man's natural and cultural bondage. We cannot jump over our own shadow. General Systems Theory is perspectivistic, not a "nothing-but" philosophy but a view that is tolerant of other philosophies and experiences"

The history of humankind has been and still is very often bloodstained with the horrors perpetrated by believers in one or another kind of absolute truth, such as those of the Inquisition, the Reign of Terror, the Third Reich,.... In the Perspectivism proposed by Bertalanffy the validity of knowledge depends on the perspective from which that knowledge is perceived. It represents a world rich with the truth of many perspectives. It helps to comprehend the fallacy of absolutism. This perspectivism approves in fact the Socrates' maxim that the learned person is someone who is aware of his or her ignorance. It is indeed necessary, for any human to maintain continuously open his mind to valuable new ideas, those that are generated by other minds trying also to comprehend the reality, each one through a particular discipline. The multidisciplinary views of any aspect of the whole reality make possible always its interdisciplinary assessment which may lead consequently to its transdisciplinary comprehension.

Humans must learn (consistently with themselves and congruously with their terrestrial environments) to develop their individual and collective capabilities, for grasping scientifically the knowledge needed for dealing properly with every natural, psychological, social and cultural situation taking into account, when necessary, how every situation is embedded in other(s) situation(s). But bearing in mind that every scientific endeavor is biased by the original decision to engage in that particular attempt. A denial of the existence of such fundamental bias, said LvB amounts to hypocrisy or moral idiocy.

"The work of science is but a humble way to redraw a few traces of the great blueprint of creation." However, the scope of inquiry, when studying science, should be pointed away from the unanswerable why of life and towards the how, while it is taken into account that the accomplishments of science are products of human observation inspired by theories conceived and built by humans. The principles that seem to govern the movement in time and in space of every aspect of the whole reality are always the outcome of human modelling; which is a human accomplishment where there is always something missing or something distorted and even wrong, because everything in any modelling is dependent from the perspective it was created. However, when trying to do something in any domain the system practitioner must understand first how the whole system is evolving.

The scientific community might help indeed to cope with the always increasingly complexity of every human concern, which is generated through the necessary integration of more and more aspects of more and more human experiences. Such a task can only be carried consistently in accordance with the Bertalanffian perspectivism. Briefly it means first of all to grasp every day the truth of additional systemic views of everything on the earth and even under the sun and secondly to search new ways of increasing and improving the comprehension that every human needs about the human species and its surroundings. A comprehension that can be acquired gradually only by means of transdisciplinary knowledge.