What language is has been one of the most problematic questions in both science and philosophy for millennia. A detailed scientific answer to this question matters greatly as it is sometimes claimed that what makes us human is language. It is widely held that language is a communication system but there is compelling evidence available suggesting that the language design favors computational efficiency over communicative efficiency in every case known. The present work attempts to show that despite prevailing beliefs, communicative concerns cannot be a factor in language design. Instead, by providing a biolinguistic and minimalist framework within which a myriad of Persian constructions are analyzed (e.g. minimal structural distance versus minimal linear distance, the subjacency condition and island violations, structural ambiguities, the copy theory of movement and extraposition), it attempts to show that language is essentially an instrument of thought and that syntax, the most powerful engine of the language faculty (FL), evolved very suddenly and abruptly in evolutionary timeline and therefore not a succession to animal communication system.