With regard to the natural sciences it is humanity's universal interest in the technical control of nature that yields the meanings of statements made by these sciences. This cognitive interest establishes rules for the construction of these sciences' instrumental theories and for their critical testing. This is the cognitive interest that Jurgen Habermas discusses in some of his work. It is one (instrumental reason) of the three knowledge-constitutive interests that he claims exist.
The materialist assumption underlying the above conception is that humans, of necessity, act on nature in order to reproduce themselves through the provision of food, instruments of production and shelter. This is called human production. It shapes and determines the surrounding world of humanity thereby changing facts and creating new ones. This dialectical anthropological assumption is a transhistorical assumption. But human instrumental action on nature takes on different forms. These forms change over time thereby giving them a historic character. Accordingly these changes must lead to changes in the characteristics of instrumental reason --such as scientific revolutions.
This assumption provides the ontological foundation for the emergence and development of instrumental knowledge culminating in natural scientific knowledge. In other words ontology constitutes the source of epistemology. This ontological assumption precludes the justification of relativism and even empiricism.
If the scientific method is merely based on facts then it follows that these facts are experienced through a conceptual system. The system influences, if not determines, the facts perceived by humanity. This means that there obtains no criterion against which to evaluate and test these facts and their corresponding conceptual framework. Relativism is thereby facilitated. Under these conditions there can exist no truth nor knowledge. Everything is relative.
The materialist conception of science, referred to, blocks off relativistic and empiricist theories of knowledge. This materialist philosophy of science provides the natural sciences with a materialist anthropological foundation from which to render science and its development secure. It also supplies the dynamic for qualitative change in instrumental cognition by rooting it in a dialectical ontology --ontology in the form of an active historical anthropology.
The materialist philosophy of science does not constitute a denial of objective reality. The point is rather that what we know about nature is always ultimately defined by the cognitive interest in manipulating nature in order to materially sustain and develop our humanity. It is this materialist anthropological condition that informs natural scientific inquiry. In this domain our cognitive interest is fundamentally instrumental. Nature is conceived, even in the theoretical and pure sciences, in terms of our interest in controlling it. It is this that gives instrumental reason its inherent teleological character. This means, in the Kantian sense, that knowledge and theory are never pure.
The materialist conception renders the justificiation of an empiricist ontology, of an independently existing world of things, impossible. This thereby renders the correspondence theory of truth unjustifiable. This is a theory of truth in which every atom of knowledge must correspond with every atom of independently existing substance.
Now facts cannot exist independently of the observer. The facts observed are, as already indicated, determined by the conceptual system through which they are perceived. It is our universal cognitive interest in the technical control of nature that constitutes the conceptual framework by which facts are observed. This ontological context for epistemological relationships prevents the justification of the existence of a plethora of random disconnected scientific conceptual systems lacking any necessary linkage to each other. However this does not mean that just one absolute conceptual system will prevail. A series of different scientific conceptual systems may historically emerge that are necessarily linked to each other. Due to these historical and cognitive developments scientific revolutions may take place. But they cannot be, as with relativism, independent of each other in a discontinuous fashion. Their discontinuous appearance can only be justified on mystical grounds. They are still essentially based on the same cognitive interest. The diverse conceptual paradigms reflect the ontological development of this same essential cognitive interest.
Logical positivism, on the other hand, seeks to establish facts as absolute by assuming that there exists one absolute conceptual framework. I chose logical positivism because of its relative simplicity while, unlike older empiricism, it includes symbologic logic. It denies the existence of more than one conceptual system by claiming that scientific inquiry is the only valid and legitimate epistemological activity. Their opinion is that there is only one basic form of scientific inquiry and thereby one instrumental conceptual system. Other systems, non-scientific, are no more than mere nonsense. Such a philosophy of science can only but restrict human freedom and is therefore oppressive. This means that humanity does not matter and cannot count as serious in relation to identifying and analysing the facts. Consequently this allows logical positivism to disregard them. This means that we establish raw data by means of the perception of the senses. Out of these sense-data, through logical construction, scientific knowledge is produced. For positivism then, philosophy's job is to define, clarify and develop the structure and logic of the natural sciences.
The materialist conception of science and positivism fundamentally differ concerning the basis for the acquisition of scientific knowledge. Consequently there can be no common ground between them.