Arjuna’s son, Abhimanyu, proved that half knowledge can have an adverse impact. He had learnt, while in Subhadra’s womb, how to enter the ‘Chakravyuh’ (a wheel formation used in wars to trap the opposition) but not how to get out of it. As a result, he was killed mercilessly, during the Kurukshetra war, when he entered the ‘Chakravyuh’ to fight against the Kaurava warriors.
The Mahabharata teaches us that one should be careful when practicing one’s application of knowledge in real life, to seek entire knowledge and not to blindly trust your resources, as you never know when they will fail.