FF-ONT)<br>
</h1>
<div style="text-align: justify;">According to <a
 href="http://www.m-w.com/cgi-bin/dictionary?logic">Merriam-Webster</a>,
logic
is the science that deals with the
principles and criteria of validity of inference and demonstration. It
is the science of the formal principles of reasoning. A <a
 href="http://plato.stanford.edu/entries/logic-classical/">logic</a>
consists
of a first order language of types, together with an axiomatic system
and a model-theoretic semantics.
<br>
</div>
<h2><a 