Human knowledge is founded on instinctive belief. It is this common sense belief that leads us to believe in an independent external world. This belief creates no difficulty for us. Neither have we any good reason to reject it since it simplifies and systematizes our experiences. Every principle of simplicity indicates that there are objects other than ourselves and our sense-data. They don’t depend on our continued perception of them. We start with what we can be certain of --our immediate experiences. We may doubt the table’s physical experience but not the sense-data that lead us to think there is one. There are grounds for thinking that these do indicate the existence of physical objects.
We have no reason for accepting the view that life is a dream. This is because life as dream is more complicated than the common-sense one of external objects as source of our sensations. Intuitive knowledge is the basis of our knowledge of truths. Intuitive knowledge are beliefs for which we cannot give reasons. They are blindingly evident general principles such as the inductive principle and general logical principles. We know them instinctively or intuitively. These primitive intuitions are a product of the evolution through natural selection of the Stone Age human brain. The genetic make-up of the human brain hardwires this bundle of intuitions in us
There are two forms of knowledge. Knowledge by acquaintance and knowledge by description. Knowledge by acquaintance involves our direct awareness of things while knowledge by description is a derivative form of knowledge based in instinct. It concerns truths about things. We are acquainted with sense-data and memory. Sense-data is that which is given by the senses such as colours and sounds.
There is also acquaintance through introspection. For example we are not directly acquainted with the table as a physical object. However our knowledge of it as a physical object is connected to our acquaintance with the sense-data that makes up its appearance. On the basis of our acquaintance with these we can formulate a description of the table or other objects which applies to only one object. Description makes it possible to go beyond private experience giving us knowledge of things we have not experienced. It also creates and develops a community of knowledge. Our acquaintance with sense-data enables us to infer the existence of physical objects and the external world. This is how we transcend our own private experience while establishing communal relations.
To draw the relevant inferences there must exist general laws and principles. We rely on the principle of induction for predicting future events. The inductive principle enables us to extend our knowledge beyond the extremely limited sphere of our private experiences. General scientific principles depend on the inductive principle. Logical principles such as the Laws of Thought have to be accepted for any argument or proof to be possible. Again this constitutes one of the epistemic conditions for transcending private experience and establishing community. Since knowledge is a priori it can be known independently of experience. Mathematical and logical principles are examples of it. Experience cannot prove that mathematical and logical principles are true. Yet it is experience that elicits a priori knowledge through particular experiences. Through experience we become aware of these general principles. All applications of a priori general propositions involve an empirical element. Human knowledge is a combination of the empirical and the a priori. It is this combination that creates the conditions for communal knowledge that transcends private knowledge.
In my view much of mainstream Marxism tends to ignore this combination and over-emphasise the experiential aspect of knowledge lending itself to some form of crude empiricism.
Much of the above was inspired by the analytical philosopher, Bertrand Russell. Much of his philosophy has been of enormous significance. Even to this day much of his philosophy is still underestimated. It was eclipsed, in varying degreest, by younger philosophers and by some of his peers such as Wittgenstein and probably Carnap. And In Ireland mainstream Marxism is more influenced by continental philosophy than it is by analytical philosophy. Given that without modern symbolic logic, a product of analytical philosophy, there would have been no large scale computer technology in existence today we see its significance. The same cannot be said for the non-analytical philosophy continental philosophy.