Complex sentence: Particularists tend to "maintain that the similarities deciphered by comparativists are vague and superficial", while comparativists tend to "contend that the differences etched by particularists are trivial and incidental".
Split into simpler sentences: Particularists tend to "maintain that the similarities deciphered by comparativists are vague and superficial". While comparativists tend to "contend that the differences etched by Particularists are trivial and incidental".