People's quotations


Criterium for Truth

Criterium for truth. Then comes the second stage in the process of cognition, the stage leading from consciousness back to matter, from ideas back to existence, in which the knowledge gained in the first stage is applied in social practice to ascertain whether the theories, policies, plans or measures meet with the anticipated success. Generally speaking, those that succeed are correct and those that fail are incorrect, and this is especially true of man’s struggle with nature . Furthermore, Man’s knowledge makes another leap through the test of practice. This leap is more important than the previous one. For it is this leap alone that can prove the correctness or incorrectness of the first leap in cognition, i.e., of the ideas, theories, policies, plans or measures formulated in the course of reflecting the objective external world. There is no other way of testing truth. ( marxist.org)

This view constrasts drastically with what some philosophers defend. Take Spinoza, according to whom truth is its own measure, that is possessing truth is fully enough to be ascertain of its correcteness. Such truth, he said in his ethics, is reflected by ideas such as the the idea that the angles on a triangle add up to two rights. First, nowadays we know this is wrong on spaces with positive curvature, in which case the angles add up stricly greater than two rights, first point. The second point is that, Spinoza implicitly defends the existence of some absolute reality that is not changing with times, aka. those ideas that he considers springing from God's Intellect, i.e. ideas that are true and eternal. This view is somehow reflexive. Where do these ideas come from? Spinoza replies, in God, in Nature. Spinoza was able to get rid of the anthropomorphic God, yet he did not push his ideas further by defeating totally idealism and embracing fully materialism. But, that is quite making sense since he lived in a era that was still under Church strong domination.


So, the truth of ideas, theories, plans, policies can only be known through the test of practice, and by this alone ( Praxis .) The same can be applied to mathematics. What is the practical reality of mathematics? The practical reality of mathematics is \( \mathbb{N} \) that we can extend up to \( \mathbb{R}\) mathematicians still struggle to understand. All mathematical theories should be tested through the lens of natural integers. This is why constructive mathemtics is the correct framework for practising mathematics because the existence of mathematical objects should be certified by the practical mathematical reality embodied in the natural integers, i.e. mathematical utlimate reality through which we can check the effectiveness of any mathematical theory. This is more and more relevant nowadays as we advance more and more to computer era.