Subject/Object

In an essay on the philosophical significance of modern science, Heidegger insists that Descartes did not “subjectivize” knowledge or metaphysics with his cogito . Much more the opposite, since Descartes was guided, Heidegger says, by the prior conviction that mathematics provided both a fundamental ontology and a fundamental epistemology.

Rather than “subjectivizing” knowledge, Descartes introduced a revolution in the meaning of “subject” and “object.”

“Until Descartes every thing at hand for itself was a ‘subject’; but now the ‘I’ becomes the special subject, that with regard to which all the remaining things first determine themselves as such. Because – mathematically – they first receive their thingness only through the founding relation to the highest principle and its ‘subject’ (I), they are essentially such as stand as something else in relation to the ‘subject,’ which lie over against it as objectum . The things themselves become ‘objects.’”

As a result, the meaning of “object” also changes: “up to then the word objectum denoted what one cast before himself in mere fantasy: I imagine a golden mountain. This thus-represented – an objectum in the language of the Middle Ages – is, according to the usage of language today, merely something ‘subjective’; for ‘a golden mountain’ does not exist ‘objectively’ in the meaning of the changed linguistic use. This reversal of the meanings of the words subjectum and objectum is no mere affair of usage; it is a radical change of Dasein, that is to say, of the lighting of the Being of beings on the basis of the predominance of the mathematical.”