A method for analyzing a thought system of a subject consisting of at least one individual is disclosed. The analyzing method comprising the steps of: obtaining a plurality of items perceived by the subject; obtaining relationship information of all possible item pairs based on perception of the subject with respect to relationship between two items of each of said all possible item pairs; generating a relation matrix of the plurality of items based on the relationship information of each of the items with respect to the all other items; transforming the relation matrix to a display matrix projected on a representation space having dimensions lower than the number of the items and reflecting a relationship between the items perceived by the subject; and displaying the items on the representation space according to the display matrix such that the items are plotted on respective positions in the representation. An apparatus for analyzing a thought system of a subject which is adapted to perform the present analyzing method is also disclosed.