Assess the difference between analytic and synthetic truths

Analytic and synthetic truths are two terms coined by Kant in the 18^th century and are used to distinguish propositions. The idea of analyticism is also used to ground a priori propositions by having something that defines them as solid as the argument of sense experience for a posteriori propositions. Kant defined analytic truths to be ones in which the predicate is contained by the subject such as ‘A triangle has three sides’. In this example the subject is the triangle and the predicate is that it has three sides. According to containment, what makes this statement an analytic truth is that it is part of the concept of a triangle that it has three sides. Moreover, Kant defined synthetic propositions as those in which the predicate is not contained in the subject such as ‘Some sisters are blonde’. This statement is true but it is synthetic because being blonde is not part of the concept of being a sister.             
Kant further defined the difference between these two types of propositions using the idea of contradiction. He said that denying an analytic truth would involve a person in contradiction whereas denying a synthetic truth could be wrong but would not be contradictory. This is illustrated by the analytic truth ‘All mothers have children’ because one could not deny this without contradicting themselves. Furthermore, the synthetic truth ‘Some mothers have brown hair’ is true and therefore you would be wrong if you denied it, but you would not be in contradiction.             
Quine felt that there needed to be further definition of these terms to make sense of them and he defined an analytic proposition as one which is true by virtue of it’s meaning and a synthetic proposition as one which is true by how its meaning relates to the world. For example, the analytic proposition ‘a bachelor is an unmarried man’ is true because an unmarried man is what the word bachelor means. Whereas the synthetic truth ‘some sisters are blonde’ is true because it portrays a feature of the world that is true; that some women who are sisters, are also blonde.