Jerry A. Fodor's Language of Thought (LOT) hypothesis, or LOTH, states that cognition and cognitive processes are only 'remotely plausible' when expressed as computational in terms of representational systems. He uses empirical data drawn from linguistics and cognitive science to express internal representations through a philosophical vantage point. Like other languages, it contains its own syntax as well as semantics which have a causal effect on the properties of these mental representations. Fodor believed that there was merit in characterizing the representational system that one was 'provisionally committed' to, and that research strategies, if not necessarily true, at least contain an 'air of prima facie plausibility.' The hypothesis describes that thoughts are represented in a "language" (sometimes known as mentalese) which allows complex thoughts to be built up by combining simpler thoughts in various ways. It is clear from the biology of the brain that these mental representations are not present in the same way as symbols written on paper; rather, the LOT is supposed to exist at the cognitive level, the level of thoughts and concepts. For example the thought that "John is tall" is clearly composed of at least two sub-parts: the concept of John (the person), and the concept of tallness. The manner in which these two sub-parts are combined could be expressed in first-order predicate calculus.