»Basic principles of curriculum and instruction« book by Ralph Tyler is the most challengeable work in the field of curriculum that has been criticized with various groups. Some of them believe it is a plagiarism and others view it’s questions as a basic for curriculum engineering. Exploring divers ideas toward the Rational and reappraise by comparing it and it's revision are two main purposes of the study in order to answer to appraise with writer. So, researcher as a appraiser, comparator and providing alternative has used philosophical inquiry (ampliative criticism) method to clarify goal based curriculum introduced by Tyler. Findings show Tyler Rational present advantages such as, emphasizing on values and individual differences .Educating on reflective teacher and reflective student, accenting on students interesting, coincidently attention on specialized training and public education, Integrating theory and practice, affirming problem solving and disadvantages as, neglecting process based evaluation, unconcern to student participating in learning strategies selection, accenting on prescriptive goals. Consequently, Rational is as a guide line for curriculum development That It’s framework components is either rigorous or flexible.