Before proceeding with any action, it is the duty of the assessing officer to arrive at a conclusion, as to whether, there is an undisclosed income under Section 2(11) and a duty is cast on the assessing officer to form an opinion, under Section 2(11). Expression, “undisclosed source of investment” depends on the existence of the above and the opinion is dependent on each one of the facts. Show cause notice issued is totally extraneous to Section 2(11) of the Act. At this juncture, it is pertinent to consider, what “satisfaction” means. “Satisfaction” means to be satisfied with a state of things, meaning thereby, to be satisfied in one’s own mind. Satisfaction is essentially a conclusion of mind. The word “satisfied” means, “makes up its mind”