ARGUMENT NO.3(D o Some writers have emphasized the apparent mismatch between the sentential structure of propositional attitudes on the one hand, and the actual neurological structures of the brain on the other hand. whereas the former involves discrete symbols(离散符号) and a combinatorial syntax (组合句法), the latter involves action potentials (动作电位), spiking frequencies(脉冲频)and spreading activation(激活扩散). As Patricia Churchland(1986) has argued, it is hard to see where in the brain we are going to find anything that even remotely resembles the sentence-like structure that appears to be essential to beliefs and other propositional attitudesARGUMENT NO.3 (II)  Some writers have emphasized the apparent mismatch between the sentential structure of propositional attitudes on the one hand, and the actual neurological structures of the brain on the other hand. Whereas the former involves discrete symbols (离散符号) and a combinatorial syntax (组合句法), the latter involves action potentials （动作电位）, spiking frequencies （脉冲频） and spreading activation （激活扩散）. As Patricia Churchland (1986) has argued, it is hard to see where in the brain we are going to find anything that even remotely resembles the sentence-like structure that appears to be essential to beliefs and other propositional attitudes