Thinking is positing or identifying something against something else. By the act of thinking itself, we are negating that which we are thinking against. Therefore, thinking is both positive and negative. Then, reasoing, a coherent process of thinking, has also a contradictory element by and in itself, because it affirms a point by affirming the counter-point that reasoing tries to discredit in the first place. Reason is not to deny a counter-point but to be aware of what its counter-point is. Thus, identity is also non-identity. Knowing what we are not makes us what we are. Therefore, if there is no otherness, there is none. The elimination of otherness is the elimination of sameness. Otherness is in sameness, and sameness is in otherness. This is the legitimate limit of reason. It is as it is and as it should always be unless it wishes to destory itself by denying its otherness.
For this, I owe a debt to Adorno’s ‘Negative Dialectics’.