What does it mean to think? There are a few questions that can seem more obvious and more complicated at the same time. The most ancient memory that preserves our civilization regarding a concrete attempt at an answer is certainly that of Parmenides. “The same is thinking and being” we find written in one of the most famous fragments of the pre-Socratic philosophical tradition.
The effort of definition that Parmenides made was the first of a long series and the thought in its essence has always remained a fundamental question around which very few philosophers failed to devote themselves.
The two great thinkers of the Greek tradition, Plato and Aristotle, saw in thought that quality which makes men the point of contact between matter and the divine. Animals cannot think and gods are thought in its purity; men, in their exceptional ontological position, are the wonderful middle way that allows the matter to return to the divine and the divine to give meaning to its infinite perfection. Aristotle goes so far as to say, in one of the most famous passages of his Metaphysics, that “If the divine Intelligence is what is most excellent, it thinks itself and its thought is thought of thought.” [Metaph., 1074b 15].
The theory of the genesis of Aristotle’s thought will remain among the theories of more complex interpretation during all its exegetical tradition. The results achieved by Averroè in his attempt to reconcile the philosophy of the Stagirita with the Islamic religion remain famous. Averroè had described the activity of thought as an action that cannot fail to interest the divine; indeed it is the divine that is the true protagonist of thinking. Thought thus becomes a tension of the intellect towards God, so much so as to lead the thinker to say “he who thinks is immortal, he who does not think dies”, referring to the fact that thinking participates in the activity of the divine and therefore in the immortality that the marks.
For Christianity it was Tommaso d’Aquino who resumed the work of Aristotle, beginning that long period of encounter/clash between reason and faith that never ceased to shake Europe until it reached extreme conclusions like the burning of Bruno.
It will be necessary to arrive at the seventeenth century to witness a clear shift in perspective that strongly brings the discussion from the divine to the human. Descartes is the true protagonist of this historical reversal that knew not only to define thought without divine attributes but even to make the same thought the essential figure of every certainty. Thought returns to a sort of Parmenidean correspondence with being, moving however from an ontological level to a strictly gnoseological one. Thinking is the absolute foundation of the philosophy of Descartes and has the power, according to the French, to anchor being to certainty without fearing the challenge of the most convinced skeptics.
A major turning point, certainly, that of Descartes but absolutely inadequate and it will not take long for an argument to arise that puts the Cartesian edifice in difficulty in its image of a solid point of arrival. The opposition will come from shores very close to Descartes and the thinker who can perhaps be considered among his greatest rivals: Pascal. It will indeed be Pascal himself who will move the Cartesian argument towards his open side: it is true that thought is the essential cornerstone of human nature but then this thought, what is it?
Pascal’s commitment often navigates towards an embittered and suspended horizon and to combine a question mark with what was the only certainty to which the philosophical path seemed to have reached perfectly fits into his system of intentions. The question then fulfills its role and seeks answers in the minds of other great thinkers. The spiritualist strand concentrated with commitment in the search for an answer to this question and succeeded in constructing a metaphysics that, starting from these shores, was directed towards Christian results. Maine de Biran will see thought as a sort of “intimate sense” that transcends all sensitivities allowing the man to reflect on it. This continuous reflection of consciousness would thus become the source of all religious security.
Thought ceases to be a certainty as unquestionable in its subsistence and becomes the origin of inner peace and a continuous tension towards God. It seems evident that a similar system of thought does not arrive at religious results spontaneously but finds its own in these are the premise and the stimulating factor. In an attempt, therefore, to move against the positivist and sensist currents that arose from the Cartesian conjectures there was the risk of returning to a matter climax-God of Platonic memory.
The big turning point comes with German thought and Kantian Ich denke. The human mind is vivisected by itself in search of the formal architectures of thought. “I think” is the foundation of the unifying act in the actuality of perceiving and I have to think of myself as identical in order to understand the possibility of the apperceptive and therefore of thought itself. The thought is no longer the immaterial effect of a substance, it is no longer a metaphysical principle or the essence of a deity; thought is a function. With Kant, thought becomes the essential function of all knowledge as such, an unavoidable logical principle that actively builds knowledge and knowledge-based on structures that make it possible. Thought builds our world and makes it knowable by framing it in constructions that allow us to represent everything through concepts.
Thought becomes with Kant the center of gravity around which orbits every possible form of knowledge. Thought when it reflects on itself does not project the outlines of an inconsistent perfection out of itself but instead rediscovers its structures in the form of a limit. Nothing that is not structured and unified in the Ich denke can be known. Much can be thought of and not understood, but the task of man-who-knows must not be to extend his own epistemological power beyond the boundaries that characterize him, but on the contrary to want to ensure in every moment the most complete autonomy concerning to what happens within those limits.
Kant’s is a complete reliance on thought, a trust upon which idealism will spread all its speculative power. Hegel dispels all sorts of subsistence under the power of the intellect: the complete self-evidence of thought with respect to itself becomes the culmination of a totalizing evolutionary process. Everything is resolved in thought without exclusions in a metaphysical circle that is born and dies in instances of pure logical intelligence.
Idealism preaches a preeminent thought, able to include every instance and every reflection in a coherent and functional system with complicated but functional architecture. Towards the end of the nineteenth century, however, idealism knows its antithesis and enters a profound crisis from which strong intellectual inclinations will arise that will characterize the twentieth century and lead us to our contemporaneity.
The concept quickly loses the primacy of essence, metaphysical certainties fall and thought is downgraded to a mere means by which the human species has found its own way to survive. Nietzsche stands in the image of this tendency and becomes a sort of prophet: thought must lose its primacy because this is only the rejection of man regarding his physical and bodily dimension. Man must return to the dynamic and exciting force of his power and physical will (which he accumulates to the earth), and no longer claim to impose pure and intellectual forms that embellish his earthly situation. God is dead and with him all the transcendence in which man has always wanted to put his hopes and weaknesses, often referring to the mysterious and impenetrable nature of thought.
The study of thought becomes ever more careful and critical in the twentieth century. The complicated debate about psychologism begins (just mention Husserl) and the abilities of the human intellect are taken beyond the space-time limits that characterize it. Logic tries to control the possible world (Frege) while science tries to exercise its dominion over nature. The twentieth century is certainly the century of science and technology and it will be Heidegger who is concerned about the relationship between science and thought. “Science does not think”, this is the famous phrase with which Heidegger tries to stimulate the contemporary debate, instigating him not to identify thought with that computation and quantifying typical of scientific reflection.
Removing every incorporeal instance from thought to project it and identify it with the expression then becomes the cornerstone of the philosophical system of another great preceptor of the twentieth century: Wittgenstein.
In our time the powerful means made available by technological evolution have allowed us to re-evaluate the question in terms of cognitive science. What is conscience? This is how Dennet decides to pose the problem, trying to show how the powerful legacies of Cartesianism prevent us from accepting the great revelations that neuroscience is giving us.
But the reality is that even Dennet comes to a standstill in his treatment. The questions remain and it is not yet clear in what terms this apparently essential figure of human nature can be defined. The thought is a problem that has more than two thousand years of research and comparison behind it, a fascinating story that highlights the great questions and fears of the human being.
This story, however, gives us a certainty: the conviction is alive in us that answering the question “What does it mean to think?” It also means answering the question “What are we?”.