CET provides a characterization of the notion of a feasibly computable function discussed in  Section 1 which is similar in form to Church’s Thesis. The corresponding thesis for decision problems holds that a problem is feasibly decidable just in case it is in the class \(\textbf{P}\). As just formulated, however, CET relies on the informal notion of a reasonable model of computation. A more precise formulation can be given by replacing this notion with a specific model such as \(\mathfrak{T}\) or \(\mathfrak{A}\) from the first machine class as discussed in   Section 3.1 below.