Before concluding that the severe intellectual limitations of the taxpayer's son rendered him incapable of performing such mental tasks as would enable him to function independently and with reasonable competence in everyday life, Bowman TCJ. found that the "and" in s. 118.4(1)(c)(ii) should be treated in context as disjunctive rather than conjunctive, and engaged in an extensive discussion of the meaning of the terms "thinking", "perceiving" and "remembering".