The Yetzer Hara is all air
The Yetzer Hara is all air, and by using your head, you can conquer him without a major battle in your heart. However, this is only true if you guard your eyes carefully. Once the eyes start to see, the heart starts to lust, and the battle switches over from being in the mind to being a much more difficult battle of the heart. Therefore, a person must make boundaries for themselves! Accept upon yourself to stop doing the things that cause the heart to become aroused. Install a fool proof filter! Stop watching movies, they are full of things that awaken the heart to lust. Stop reading non-Jewish magazines and newspapers. Learn to guard your eyes in the street. You MUST make boundaries if you are to make any progress! Otherwise, no matter how "smart" you are and no matter how much you are convinced in your mind of the folly of these desires, the heart will still wage a merciless battle. But if you guard the eyes, then the battle can remain only in the realm of the mind, where it is much easier to win!