Appeal No. 95-4010 Application 08/082,338 The Examiner has failed to show that the prior art suggested the desirability of the Examiner's proposed modification. Tanagawa teaches that the need of the prevention circuit is not because of a presence of an inoperable instruction. Instead, Tanagawa teaches that the prevention circuit provides a measure for prevention of an erroneous operation of the computer when an instruction may be converted to another operable instruction due to undesirable environments. Tanagawa does not suggest to those skilled in the art to test the operational validity of the instruction before it is executed. We cannot find that Appellants' invention is obvious just because the Examiner puts together the Appellants' invention using the Appellants' application as a road map. This hindsight view is not evidence that those skilled in the art would have reason to make the modification. We are not inclined to dispense with proof by evidence when the proposition at issue is not supported by a teaching in a prior art reference or shown to be common knowledge of unquestionable demonstration. Our reviewing court requires this 9Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 NextLast modified: November 3, 2007