''I think, therefore I am'', Descartes.
Bingo!
With greater accuracy than the "cogito ergo sum" (I think therefore I am) the Jewish concept of language expresses the fact of the objectively realistic existence in "cogitor ergo sum" (thought, therefore I am), I am the object of thought, therefore I am. I "am" only so long as I am the object of thought. My existence is dependent on the conception of a Higher Being whose object of thought I am.
Rabbi Samson R. Hirsch, Collected Writings Vol. 8, p. 25.
Our bodies as material objects inhabit the empirical world. However, there is a part of our selves which can initiate movements of our bodies at will, independently of the laws of physics (though not, of course, contrary to the laws of physics) and which must therefore be outside the empirical world. How it does it – what the relationship is between the willing me and the physical me – is a mystery that has baffled understanding since the beginning of human enquiry. But although I do not know what I am, I know that I cannot be only my body. I know myself to be a being that somehow combines the empirical and the non-empirical. In fact I am, so to speak, the embodied interface between the empirical and the non-empirical.
Bryan Magee, Oxford Professor of Philosophy, Confessions of a Philosopher, p. 161.
John