For logicians who want to accept only that which is proven through logic and argument, it is a fact that without logic and reason there can be no question of accepting the Absolute Truth. Unfortunately, when such logicians take to this path without the mercy of the Lord, they remain on the platform of logic and argument and do not advance in spiritual life. However, if one is intelligent enough to apply his arguments and logic to the subtle understanding of the fundamental spiritual substance, he will be able to know that a poor fund of knowledge established on the basis of material logic cannot help one understand the Absolute Truth, which is beyond the reach of imperfect senses. The Mahābhārata therefore says: acintyāḥ khalu ye bhāvā na tāṁs tarkeṇa yojayet. (Mahābhārata, Bhīṣma-parva 5.22) How can that which is beyond the imagination or sensory speculation of mundane creatures be approached simply by logic? Logic and argument are very poor in spiritual strength and always imperfect when applied to spiritual understanding. By putting forward mundane logic one frequently comes to the wrong conclusion regarding the Absolute Truth, and as a result of such a conclusion one may fall down to accept a body like that of a animal.
Ref >> Srila Prabhupada Vani.